{"items":[{"id":"NVI-00005950","kind":"vulnerability","title":"league/commonmark XSS: `on*` event-handler filter in `AttributesExtension` bypassed with a U+000C form feed","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-f8fg-pg57-v4j8","CVE-2026-86431"],"plain_summary":"OSV carries this publisher advisory for league/commonmark. 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 2.9.1 for league/commonmark. Confirm the publisher’s latest guidance.","source_ids":["sr-a2476451ee4934b5649b449a1651f8fb"],"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":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-2dd74c49e0ed49507886976a6d87830f"],"action_type":"investigate","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":[{"kind":"CVSS","as_of":"2026-10-08T16:17:57.507Z","value":"7.2 HIGH (3.1)","meaning":"disclosure@vulncheck.com severity; no combined Null risk score.","source_id":"sr-8d05486146b4b376945dec52bfcf99c9"},{"kind":"CVSS","as_of":"2026-10-08T16:17:57.507Z","value":"6.9 MEDIUM (4.0)","meaning":"disclosure@vulncheck.com severity; no combined Null risk score.","source_id":"sr-8d05486146b4b376945dec52bfcf99c9"},{"kind":"EPSS","as_of":"2026-11-01T12:00:16.000Z","value":"0.388%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.32925. Missing scores are unknown.","source_id":"sr-2dd74c49e0ed49507886976a6d87830f"}],"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-a2476451ee4934b5649b449a1651f8fb","url":"https://github.com/advisories/GHSA-f8fg-pg57-v4j8","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-f8fg-pg57-v4j8","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-10-31T21:42:10.711Z"},{"id":"sr-8d05486146b4b376945dec52bfcf99c9","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86431","basis":"official_catalog","notes":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","title":"CVE-2026-86431","publisher":"NIST National Vulnerability Database","observed_at":"2026-11-01T07:25:08.112Z"},{"id":"sr-2dd74c49e0ed49507886976a6d87830f","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-86431","publisher":"FIRST EPSS","observed_at":"2026-11-01T14:28:32.288Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-a2476451ee4934b5649b449a1651f8fb"],"technology":"league/commonmark","known_exclusions":[],"conditions_summary":"### Summary\n\nThe `AttributesExtension` documents a security guarantee:\n\n> **Note:** Attributes starting with `on` (e.g. `onclick` or `onerror`) are capable of executing\n> JavaScript code and are therefore **never allowed by default**. You must explicitly add them to\n> the `allow` list if you want to use them.\n>\n> — `docs/2.x/extensions/attributes.md`\n\nPrefixing the attribute name with a single U+000C FORM FEED byte defeats that guarantee.\n`{onclick=\"alert(1)\"}` passes through `AttributesHelper::filterAttributes()` untouched and is\nwritten verbatim into the output, where browsers parse it as a genuine `onclick` handler.\n\nThe same prefix defeats the `allow_unsafe_links` check, letting a `javascript:` URI through on\n`href` / `src` even when `allow_unsafe_links` is `false`.\n\nThis bypasses the fix shipped in the **2.7.0 security release** (\"Fix XSS in AttributesExtension\",\n43207253ea5f14867c77c697cd3838c446cadcea), which added `filterAttributes()` for the express\npurpose of blocking these attributes.\n\nThroughout this report `` denotes a literal U+000C byte (`\"\\x0C\"` in PHP). It is invisible in\nrendered text, so all payloads below are written with PHP escape sequences to stay una","public_affected_ranges":["ECOSYSTEM: introduced 2.7.0; fixed 2.9.1"]}],"null_published_at":"2026-11-06T15:18:11.481Z","source_updated_at":"2026-09-08T12:38:28.846Z","source_disclosed_at":"2026-09-01T20:18:29.000Z","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":"2026-10-31T21:42:10.711Z"},{"id":"NVI-00005950","kind":"vulnerability","title":"league/commonmark XSS: `on*` event-handler filter in `AttributesExtension` bypassed with a U+000C form feed","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-f8fg-pg57-v4j8","CVE-2026-86431"],"plain_summary":"OSV carries this publisher advisory for league/commonmark. 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 2.9.1 for league/commonmark. Confirm the publisher’s latest guidance.","source_ids":["sr-a2476451ee4934b5649b449a1651f8fb"],"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":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-aabeb6e1bb3f69564f2a5a12c1c6fe38"],"action_type":"investigate","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":[{"kind":"CVSS","as_of":"2026-10-08T16:17:57.507Z","value":"7.2 HIGH (3.1)","meaning":"disclosure@vulncheck.com severity; no combined Null risk score.","source_id":"sr-8d05486146b4b376945dec52bfcf99c9"},{"kind":"CVSS","as_of":"2026-10-08T16:17:57.507Z","value":"6.9 MEDIUM (4.0)","meaning":"disclosure@vulncheck.com severity; no combined Null risk score.","source_id":"sr-8d05486146b4b376945dec52bfcf99c9"},{"kind":"EPSS","as_of":"2026-10-31T12:00:27.000Z","value":"0.388%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.32929. Missing scores are unknown.","source_id":"sr-aabeb6e1bb3f69564f2a5a12c1c6fe38"}],"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-a2476451ee4934b5649b449a1651f8fb","url":"https://github.com/advisories/GHSA-f8fg-pg57-v4j8","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-f8fg-pg57-v4j8","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-10-31T21:42:10.711Z"},{"id":"sr-8d05486146b4b376945dec52bfcf99c9","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86431","basis":"official_catalog","notes":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","title":"CVE-2026-86431","publisher":"NIST National Vulnerability Database","observed_at":"2026-11-01T07:25:08.112Z"},{"id":"sr-aabeb6e1bb3f69564f2a5a12c1c6fe38","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-86431","publisher":"FIRST EPSS","observed_at":"2026-10-31T22:06:15.385Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-a2476451ee4934b5649b449a1651f8fb"],"technology":"league/commonmark","known_exclusions":[],"conditions_summary":"### Summary\n\nThe `AttributesExtension` documents a security guarantee:\n\n> **Note:** Attributes starting with `on` (e.g. `onclick` or `onerror`) are capable of executing\n> JavaScript code and are therefore **never allowed by default**. You must explicitly add them to\n> the `allow` list if you want to use them.\n>\n> — `docs/2.x/extensions/attributes.md`\n\nPrefixing the attribute name with a single U+000C FORM FEED byte defeats that guarantee.\n`{onclick=\"alert(1)\"}` passes through `AttributesHelper::filterAttributes()` untouched and is\nwritten verbatim into the output, where browsers parse it as a genuine `onclick` handler.\n\nThe same prefix defeats the `allow_unsafe_links` check, letting a `javascript:` URI through on\n`href` / `src` even when `allow_unsafe_links` is `false`.\n\nThis bypasses the fix shipped in the **2.7.0 security release** (\"Fix XSS in AttributesExtension\",\n43207253ea5f14867c77c697cd3838c446cadcea), which added `filterAttributes()` for the express\npurpose of blocking these attributes.\n\nThroughout this report `` denotes a literal U+000C byte (`\"\\x0C\"` in PHP). It is invisible in\nrendered text, so all payloads below are written with PHP escape sequences to stay una","public_affected_ranges":["ECOSYSTEM: introduced 2.7.0; fixed 2.9.1"]}],"null_published_at":"2026-11-05T03:52:54.761Z","source_updated_at":"2026-09-08T12:38:28.846Z","source_disclosed_at":"2026-09-01T20:18:29.000Z","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":"2026-10-31T21:42:10.711Z"},{"id":"NVI-00005950","kind":"vulnerability","title":"league/commonmark XSS: `on*` event-handler filter in `AttributesExtension` bypassed with a U+000C form feed","revision":2,"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-f8fg-pg57-v4j8","CVE-2026-86431"],"plain_summary":"OSV carries this publisher advisory for league/commonmark. 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 2.9.1 for league/commonmark. Confirm the publisher’s latest guidance.","source_ids":["sr-a2476451ee4934b5649b449a1651f8fb"],"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":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-8d05486146b4b376945dec52bfcf99c9"],"action_type":"investigate","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":[{"kind":"CVSS","as_of":"2026-10-08T16:17:57.507Z","value":"7.2 HIGH (3.1)","meaning":"disclosure@vulncheck.com severity; no combined Null risk score.","source_id":"sr-8d05486146b4b376945dec52bfcf99c9"},{"kind":"CVSS","as_of":"2026-10-08T16:17:57.507Z","value":"6.9 MEDIUM (4.0)","meaning":"disclosure@vulncheck.com severity; no combined Null risk score.","source_id":"sr-8d05486146b4b376945dec52bfcf99c9"}],"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-a2476451ee4934b5649b449a1651f8fb","url":"https://github.com/advisories/GHSA-f8fg-pg57-v4j8","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-f8fg-pg57-v4j8","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-10-31T21:42:10.711Z"},{"id":"sr-8d05486146b4b376945dec52bfcf99c9","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86431","basis":"official_catalog","notes":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","title":"CVE-2026-86431","publisher":"NIST National Vulnerability Database","observed_at":"2026-11-01T07:25:08.112Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-a2476451ee4934b5649b449a1651f8fb"],"technology":"league/commonmark","known_exclusions":[],"conditions_summary":"### Summary\n\nThe `AttributesExtension` documents a security guarantee:\n\n> **Note:** Attributes starting with `on` (e.g. `onclick` or `onerror`) are capable of executing\n> JavaScript code and are therefore **never allowed by default**. You must explicitly add them to\n> the `allow` list if you want to use them.\n>\n> — `docs/2.x/extensions/attributes.md`\n\nPrefixing the attribute name with a single U+000C FORM FEED byte defeats that guarantee.\n`{onclick=\"alert(1)\"}` passes through `AttributesHelper::filterAttributes()` untouched and is\nwritten verbatim into the output, where browsers parse it as a genuine `onclick` handler.\n\nThe same prefix defeats the `allow_unsafe_links` check, letting a `javascript:` URI through on\n`href` / `src` even when `allow_unsafe_links` is `false`.\n\nThis bypasses the fix shipped in the **2.7.0 security release** (\"Fix XSS in AttributesExtension\",\n43207253ea5f14867c77c697cd3838c446cadcea), which added `filterAttributes()` for the express\npurpose of blocking these attributes.\n\nThroughout this report `` denotes a literal U+000C byte (`\"\\x0C\"` in PHP). It is invisible in\nrendered text, so all payloads below are written with PHP escape sequences to stay una","public_affected_ranges":["ECOSYSTEM: introduced 2.7.0; fixed 2.9.1"]}],"null_published_at":"2026-11-03T17:49:21.367Z","source_updated_at":"2026-09-08T12:38:28.846Z","source_disclosed_at":"2026-09-01T20:18:29.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Source facts changed; compare the preserved prior revision.","null_first_observed_at":"2026-10-31T21:42:10.711Z"},{"id":"NVI-00005950","kind":"vulnerability","title":"league/commonmark XSS: `on*` event-handler filter in `AttributesExtension` bypassed with a U+000C form feed","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-f8fg-pg57-v4j8","CVE-2026-86431"],"plain_summary":"OSV carries this publisher advisory for league/commonmark. 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 2.9.1 for league/commonmark. Confirm the publisher’s latest guidance.","source_ids":["sr-a2476451ee4934b5649b449a1651f8fb"],"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-a2476451ee4934b5649b449a1651f8fb","url":"https://github.com/advisories/GHSA-f8fg-pg57-v4j8","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-f8fg-pg57-v4j8","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-10-31T21:42:10.711Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-a2476451ee4934b5649b449a1651f8fb"],"technology":"league/commonmark","known_exclusions":[],"conditions_summary":"### Summary\n\nThe `AttributesExtension` documents a security guarantee:\n\n> **Note:** Attributes starting with `on` (e.g. `onclick` or `onerror`) are capable of executing\n> JavaScript code and are therefore **never allowed by default**. You must explicitly add them to\n> the `allow` list if you want to use them.\n>\n> — `docs/2.x/extensions/attributes.md`\n\nPrefixing the attribute name with a single U+000C FORM FEED byte defeats that guarantee.\n`{onclick=\"alert(1)\"}` passes through `AttributesHelper::filterAttributes()` untouched and is\nwritten verbatim into the output, where browsers parse it as a genuine `onclick` handler.\n\nThe same prefix defeats the `allow_unsafe_links` check, letting a `javascript:` URI through on\n`href` / `src` even when `allow_unsafe_links` is `false`.\n\nThis bypasses the fix shipped in the **2.7.0 security release** (\"Fix XSS in AttributesExtension\",\n43207253ea5f14867c77c697cd3838c446cadcea), which added `filterAttributes()` for the express\npurpose of blocking these attributes.\n\nThroughout this report `` denotes a literal U+000C byte (`\"\\x0C\"` in PHP). It is invisible in\nrendered text, so all payloads below are written with PHP escape sequences to stay una","public_affected_ranges":["ECOSYSTEM: introduced 2.7.0; fixed 2.9.1"]}],"null_published_at":"2026-10-31T22:13:05.853Z","source_updated_at":"2026-09-08T12:38:28.846Z","source_disclosed_at":"2026-09-01T20:18:29.000Z","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":"2026-10-31T21:42:10.711Z"}],"next_cursor":null,"snapshot_revision":"42594"}