{"items":[{"id":"NVI-00007790","kind":"vulnerability","title":"Flarum Vulnerable to Session Hijacking via Authoritative Subdomain Cookie Overwrite","revision":5,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected.","NVD lastModified does not establish freshness of every associated CPE record."],"lifecycle":"active","identifiers":["GHSA-hg9j-64wp-m9px","CVE-2025-27794"],"plain_summary":"OSV carries this publisher advisory for flarum/core, flarum/framework. This is an aggregated source copy; consult the original publisher and compare update dates.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"The original advisory lists fixed boundaries 1.8.10 for flarum/core. Confirm the publisher’s latest guidance.","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. 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Dataset date/model retained; FIRST services terms apply.","title":"CVE-2025-27794","publisher":"FIRST EPSS","observed_at":"2026-11-04T17:58:50.301Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"technology":"flarum/core","known_exclusions":[],"conditions_summary":"## **Summary**  \nA session hijacking vulnerability exists when an attacker-controlled **authoritative subdomain** under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication.  \n\n**Key Constraints**:  \n- Attacker must control **any subdomain** under the parent domain (e.g., `evil.host.com` or `x.y.host.com`).  \n- Parent domain must **not** be on the Public Suffix List.\n\nDue to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described.\n\n---\n\n## **Proof of Concept (Deno)**  \n```ts\nDeno.serve({\n    port: 8000, // default\n    hostname: 'localhost',\n    onListen: (o) => console.log(`Server started at http://${o.hostname}:${o.port}`, o),\n  },\n  async (req) => (console.log(req), new Response(\n    `You've been served! You came from ${req.headers.get('referer')}`,\n    {\n      //status: 30","public_affected_ranges":["ECOSYSTEM: introduced 0; fixed 1.8.10"]},{"certainty":"source_listed","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"technology":"flarum/framework","known_exclusions":[],"conditions_summary":"## **Summary**  \nA session hijacking vulnerability exists when an attacker-controlled **authoritative subdomain** under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication.  \n\n**Key Constraints**:  \n- Attacker must control **any subdomain** under the parent domain (e.g., `evil.host.com` or `x.y.host.com`).  \n- Parent domain must **not** be on the Public Suffix List.\n\nDue to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described.\n\n---\n\n## **Proof of Concept (Deno)**  \n```ts\nDeno.serve({\n    port: 8000, // default\n    hostname: 'localhost',\n    onListen: (o) => console.log(`Server started at http://${o.hostname}:${o.port}`, o),\n  },\n  async (req) => (console.log(req), new Response(\n    `You've been served! You came from ${req.headers.get('referer')}`,\n    {\n      //status: 30","public_affected_ranges":["ECOSYSTEM: introduced 0; fixed 1.8.10"]}],"null_published_at":"2026-11-08T08:10:32.023Z","source_updated_at":"2025-03-12T22:12:10.626Z","source_disclosed_at":"2025-03-12T22:06:16.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-10-31T21:42:20.429Z"},{"id":"NVI-00007790","kind":"vulnerability","title":"Flarum Vulnerable to Session Hijacking via Authoritative Subdomain Cookie Overwrite","revision":4,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected.","NVD lastModified does not establish freshness of every associated CPE record."],"lifecycle":"active","identifiers":["GHSA-hg9j-64wp-m9px","CVE-2025-27794"],"plain_summary":"OSV carries this publisher advisory for flarum/core, flarum/framework. This is an aggregated source copy; consult the original publisher and compare update dates.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"The original advisory lists fixed boundaries 1.8.10 for flarum/core. Confirm the publisher’s latest guidance.","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"The original advisory lists fixed boundaries 1.8.10 for flarum/framework. Confirm the publisher’s latest guidance.","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. 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Dataset date/model retained; FIRST services terms apply.","title":"CVE-2025-27794","publisher":"FIRST EPSS","observed_at":"2026-11-03T17:44:07.766Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"technology":"flarum/core","known_exclusions":[],"conditions_summary":"## **Summary**  \nA session hijacking vulnerability exists when an attacker-controlled **authoritative subdomain** under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication.  \n\n**Key Constraints**:  \n- Attacker must control **any subdomain** under the parent domain (e.g., `evil.host.com` or `x.y.host.com`).  \n- Parent domain must **not** be on the Public Suffix List.\n\nDue to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described.\n\n---\n\n## **Proof of Concept (Deno)**  \n```ts\nDeno.serve({\n    port: 8000, // default\n    hostname: 'localhost',\n    onListen: (o) => console.log(`Server started at http://${o.hostname}:${o.port}`, o),\n  },\n  async (req) => (console.log(req), new Response(\n    `You've been served! You came from ${req.headers.get('referer')}`,\n    {\n      //status: 30","public_affected_ranges":["ECOSYSTEM: introduced 0; fixed 1.8.10"]},{"certainty":"source_listed","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"technology":"flarum/framework","known_exclusions":[],"conditions_summary":"## **Summary**  \nA session hijacking vulnerability exists when an attacker-controlled **authoritative subdomain** under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication.  \n\n**Key Constraints**:  \n- Attacker must control **any subdomain** under the parent domain (e.g., `evil.host.com` or `x.y.host.com`).  \n- Parent domain must **not** be on the Public Suffix List.\n\nDue to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described.\n\n---\n\n## **Proof of Concept (Deno)**  \n```ts\nDeno.serve({\n    port: 8000, // default\n    hostname: 'localhost',\n    onListen: (o) => console.log(`Server started at http://${o.hostname}:${o.port}`, o),\n  },\n  async (req) => (console.log(req), new Response(\n    `You've been served! You came from ${req.headers.get('referer')}`,\n    {\n      //status: 30","public_affected_ranges":["ECOSYSTEM: introduced 0; fixed 1.8.10"]}],"null_published_at":"2026-11-06T00:29:57.257Z","source_updated_at":"2025-03-12T22:12:10.626Z","source_disclosed_at":"2025-03-12T22:06:16.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-10-31T21:42:20.429Z"},{"id":"NVI-00007790","kind":"vulnerability","title":"Flarum Vulnerable to Session Hijacking via Authoritative Subdomain Cookie Overwrite","revision":3,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected.","NVD lastModified does not establish freshness of every associated CPE record."],"lifecycle":"active","identifiers":["GHSA-hg9j-64wp-m9px","CVE-2025-27794"],"plain_summary":"OSV carries this publisher advisory for flarum/core, flarum/framework. This is an aggregated source copy; consult the original publisher and compare update dates.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"The original advisory lists fixed boundaries 1.8.10 for flarum/core. Confirm the publisher’s latest guidance.","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"The original advisory lists fixed boundaries 1.8.10 for flarum/framework. Confirm the publisher’s latest guidance.","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. 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Dataset date/model retained; FIRST services terms apply.","title":"CVE-2025-27794","publisher":"FIRST EPSS","observed_at":"2026-10-31T22:06:15.370Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"technology":"flarum/core","known_exclusions":[],"conditions_summary":"## **Summary**  \nA session hijacking vulnerability exists when an attacker-controlled **authoritative subdomain** under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication.  \n\n**Key Constraints**:  \n- Attacker must control **any subdomain** under the parent domain (e.g., `evil.host.com` or `x.y.host.com`).  \n- Parent domain must **not** be on the Public Suffix List.\n\nDue to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described.\n\n---\n\n## **Proof of Concept (Deno)**  \n```ts\nDeno.serve({\n    port: 8000, // default\n    hostname: 'localhost',\n    onListen: (o) => console.log(`Server started at http://${o.hostname}:${o.port}`, o),\n  },\n  async (req) => (console.log(req), new Response(\n    `You've been served! You came from ${req.headers.get('referer')}`,\n    {\n      //status: 30","public_affected_ranges":["ECOSYSTEM: introduced 0; fixed 1.8.10"]},{"certainty":"source_listed","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"technology":"flarum/framework","known_exclusions":[],"conditions_summary":"## **Summary**  \nA session hijacking vulnerability exists when an attacker-controlled **authoritative subdomain** under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication.  \n\n**Key Constraints**:  \n- Attacker must control **any subdomain** under the parent domain (e.g., `evil.host.com` or `x.y.host.com`).  \n- Parent domain must **not** be on the Public Suffix List.\n\nDue to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described.\n\n---\n\n## **Proof of Concept (Deno)**  \n```ts\nDeno.serve({\n    port: 8000, // default\n    hostname: 'localhost',\n    onListen: (o) => console.log(`Server started at http://${o.hostname}:${o.port}`, o),\n  },\n  async (req) => (console.log(req), new Response(\n    `You've been served! You came from ${req.headers.get('referer')}`,\n    {\n      //status: 30","public_affected_ranges":["ECOSYSTEM: introduced 0; fixed 1.8.10"]}],"null_published_at":"2026-11-04T10:04:35.938Z","source_updated_at":"2025-03-12T22:12:10.626Z","source_disclosed_at":"2025-03-12T22:06:16.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Source facts changed; compare the preserved prior revision.","null_first_observed_at":"2026-10-31T21:42:20.429Z"},{"id":"NVI-00007790","kind":"vulnerability","title":"Flarum Vulnerable to Session Hijacking via Authoritative Subdomain Cookie Overwrite","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-hg9j-64wp-m9px","CVE-2025-27794"],"plain_summary":"OSV carries this publisher advisory for flarum/core, flarum/framework. This is an aggregated source copy; consult the original publisher and compare update dates.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"The original advisory lists fixed boundaries 1.8.10 for flarum/core. Confirm the publisher’s latest guidance.","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"The original advisory lists fixed boundaries 1.8.10 for flarum/framework. Confirm the publisher’s latest guidance.","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. 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Dataset date/model retained; FIRST services terms apply.","title":"CVE-2025-27794","publisher":"FIRST EPSS","observed_at":"2026-10-31T22:06:15.370Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"technology":"flarum/core","known_exclusions":[],"conditions_summary":"## **Summary**  \nA session hijacking vulnerability exists when an attacker-controlled **authoritative subdomain** under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication.  \n\n**Key Constraints**:  \n- Attacker must control **any subdomain** under the parent domain (e.g., `evil.host.com` or `x.y.host.com`).  \n- Parent domain must **not** be on the Public Suffix List.\n\nDue to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described.\n\n---\n\n## **Proof of Concept (Deno)**  \n```ts\nDeno.serve({\n    port: 8000, // default\n    hostname: 'localhost',\n    onListen: (o) => console.log(`Server started at http://${o.hostname}:${o.port}`, o),\n  },\n  async (req) => (console.log(req), new Response(\n    `You've been served! You came from ${req.headers.get('referer')}`,\n    {\n      //status: 30","public_affected_ranges":["ECOSYSTEM: introduced 0; fixed 1.8.10"]},{"certainty":"source_listed","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"technology":"flarum/framework","known_exclusions":[],"conditions_summary":"## **Summary**  \nA session hijacking vulnerability exists when an attacker-controlled **authoritative subdomain** under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication.  \n\n**Key Constraints**:  \n- Attacker must control **any subdomain** under the parent domain (e.g., `evil.host.com` or `x.y.host.com`).  \n- Parent domain must **not** be on the Public Suffix List.\n\nDue to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described.\n\n---\n\n## **Proof of Concept (Deno)**  \n```ts\nDeno.serve({\n    port: 8000, // default\n    hostname: 'localhost',\n    onListen: (o) => console.log(`Server started at http://${o.hostname}:${o.port}`, o),\n  },\n  async (req) => (console.log(req), new Response(\n    `You've been served! You came from ${req.headers.get('referer')}`,\n    {\n      //status: 30","public_affected_ranges":["ECOSYSTEM: introduced 0; fixed 1.8.10"]}],"null_published_at":"2026-11-01T01:04:04.845Z","source_updated_at":"2025-03-12T22:12:10.626Z","source_disclosed_at":"2025-03-12T22:06:16.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-10-31T21:42:20.429Z"},{"id":"NVI-00007790","kind":"vulnerability","title":"Flarum Vulnerable to Session Hijacking via Authoritative Subdomain Cookie Overwrite","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-hg9j-64wp-m9px","CVE-2025-27794"],"plain_summary":"OSV carries this publisher advisory for flarum/core, flarum/framework. This is an aggregated source copy; consult the original publisher and compare update dates.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"The original advisory lists fixed boundaries 1.8.10 for flarum/core. Confirm the publisher’s latest guidance.","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"The original advisory lists fixed boundaries 1.8.10 for flarum/framework. Confirm the publisher’s latest guidance.","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-e8d833ce2646e82c0a17956b26fc6ebe","url":"https://github.com/advisories/GHSA-hg9j-64wp-m9px","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-hg9j-64wp-m9px","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-10-31T21:42:20.429Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"technology":"flarum/core","known_exclusions":[],"conditions_summary":"## **Summary**  \nA session hijacking vulnerability exists when an attacker-controlled **authoritative subdomain** under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication.  \n\n**Key Constraints**:  \n- Attacker must control **any subdomain** under the parent domain (e.g., `evil.host.com` or `x.y.host.com`).  \n- Parent domain must **not** be on the Public Suffix List.\n\nDue to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described.\n\n---\n\n## **Proof of Concept (Deno)**  \n```ts\nDeno.serve({\n    port: 8000, // default\n    hostname: 'localhost',\n    onListen: (o) => console.log(`Server started at http://${o.hostname}:${o.port}`, o),\n  },\n  async (req) => (console.log(req), new Response(\n    `You've been served! You came from ${req.headers.get('referer')}`,\n    {\n      //status: 30","public_affected_ranges":["ECOSYSTEM: introduced 0; fixed 1.8.10"]},{"certainty":"source_listed","source_ids":["sr-e8d833ce2646e82c0a17956b26fc6ebe"],"technology":"flarum/framework","known_exclusions":[],"conditions_summary":"## **Summary**  \nA session hijacking vulnerability exists when an attacker-controlled **authoritative subdomain** under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication.  \n\n**Key Constraints**:  \n- Attacker must control **any subdomain** under the parent domain (e.g., `evil.host.com` or `x.y.host.com`).  \n- Parent domain must **not** be on the Public Suffix List.\n\nDue to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described.\n\n---\n\n## **Proof of Concept (Deno)**  \n```ts\nDeno.serve({\n    port: 8000, // default\n    hostname: 'localhost',\n    onListen: (o) => console.log(`Server started at http://${o.hostname}:${o.port}`, o),\n  },\n  async (req) => (console.log(req), new Response(\n    `You've been served! You came from ${req.headers.get('referer')}`,\n    {\n      //status: 30","public_affected_ranges":["ECOSYSTEM: introduced 0; fixed 1.8.10"]}],"null_published_at":"2026-10-31T22:13:18.635Z","source_updated_at":"2025-03-12T22:12:10.626Z","source_disclosed_at":"2025-03-12T22:06:16.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-10-31T21:42:20.429Z"}],"next_cursor":null,"snapshot_revision":"42594"}