{"items":[{"id":"NVI-00016007","kind":"vulnerability","title":"js-yaml: Quadratic-complexity (O(n^2)) DoS via !!omap tag in YAML11_SCHEMA","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-724g-mxrg-4qvm","CVE-2026-59870"],"plain_summary":"GitHub lists this reviewed advisory for js-yaml. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-11881833a3270d50a7041ff2e0f244da"],"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":"2026-07-20T21:18:53.000Z","value":"5.3 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-026e8d7afc88408a52c9583fa45e7c0a"},{"kind":"EPSS","as_of":"2026-11-04T12:03:12.000Z","value":"0.740%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.54698. Missing scores are unknown.","source_id":"sr-11881833a3270d50a7041ff2e0f244da"}],"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-026e8d7afc88408a52c9583fa45e7c0a","url":"https://github.com/advisories/GHSA-724g-mxrg-4qvm","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-724g-mxrg-4qvm","publisher":"GitHub Advisory Database","observed_at":"2026-11-04T02:47:44.783Z"},{"id":"sr-11881833a3270d50a7041ff2e0f244da","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-2026-59870","publisher":"FIRST EPSS","observed_at":"2026-11-04T23:33:33.055Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-026e8d7afc88408a52c9583fa45e7c0a"],"technology":"js-yaml","known_exclusions":[],"conditions_summary":"### Summary\n`js-yaml` v5.x introduces `YAML11_SCHEMA` support with the `!!omap` (ordered map) tag. The `omapTag.addItem()` function performs a linear O(n) scan for duplicate key detection on every insertion, resulting in O(n^2) total time to parse a document with n omap entries. An attacker can send a small crafted YAML document to trigger a multi-second CPU stall in any application that uses `yaml.load()` with `{ schema: yaml.YAML11_SCHEMA }`.\n\n### Details\nIn `src/tag/sequence/omap.ts` (compiled: `dist/js-yaml.cjs.js:510-525`):\n```js\nvar omapTag = defineSequenceTag('tag:yaml.org,2002:omap', {\n    create: () => [],\n    addItem: (container, item) => {\n        // ...\n        for (const existing of container)   // O(n) per insertion!\n            if (hasOwnProperty(existing, itemKeys[0]))\n                return 'cannot resolve an ordered map item';\n        container.push(object);             // n insertions → O(n^2) total\n        return '';\n    }\n});\n```\nFor a document with `n` unique entries, insertion i scans i−1 existing entries, yielding 1+2+…+n = **O(n²)** total work.\n\n### PoC (runtime-confirmed on v5.2.0)\n```js\nconst yaml = require('js-yaml');\nfunction buildOmapPayload(n) {\n  let","public_affected_ranges":[">= 5.0.0, <= 5.2.0"]}],"null_published_at":"2026-11-07T14:02:01.404Z","source_updated_at":"2026-07-20T21:18:53.000Z","source_disclosed_at":"2026-07-20T21:18:51.000Z","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":"2026-11-04T02:47:44.783Z"},{"id":"NVI-00016007","kind":"vulnerability","title":"js-yaml: Quadratic-complexity (O(n^2)) DoS via !!omap tag in YAML11_SCHEMA","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-724g-mxrg-4qvm","CVE-2026-59870"],"plain_summary":"GitHub lists this reviewed advisory for js-yaml. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-026e8d7afc88408a52c9583fa45e7c0a"],"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":"2026-07-20T21:18:53.000Z","value":"5.3 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-026e8d7afc88408a52c9583fa45e7c0a"}],"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-026e8d7afc88408a52c9583fa45e7c0a","url":"https://github.com/advisories/GHSA-724g-mxrg-4qvm","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-724g-mxrg-4qvm","publisher":"GitHub Advisory Database","observed_at":"2026-11-04T02:47:44.783Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-026e8d7afc88408a52c9583fa45e7c0a"],"technology":"js-yaml","known_exclusions":[],"conditions_summary":"### Summary\n`js-yaml` v5.x introduces `YAML11_SCHEMA` support with the `!!omap` (ordered map) tag. The `omapTag.addItem()` function performs a linear O(n) scan for duplicate key detection on every insertion, resulting in O(n^2) total time to parse a document with n omap entries. An attacker can send a small crafted YAML document to trigger a multi-second CPU stall in any application that uses `yaml.load()` with `{ schema: yaml.YAML11_SCHEMA }`.\n\n### Details\nIn `src/tag/sequence/omap.ts` (compiled: `dist/js-yaml.cjs.js:510-525`):\n```js\nvar omapTag = defineSequenceTag('tag:yaml.org,2002:omap', {\n    create: () => [],\n    addItem: (container, item) => {\n        // ...\n        for (const existing of container)   // O(n) per insertion!\n            if (hasOwnProperty(existing, itemKeys[0]))\n                return 'cannot resolve an ordered map item';\n        container.push(object);             // n insertions → O(n^2) total\n        return '';\n    }\n});\n```\nFor a document with `n` unique entries, insertion i scans i−1 existing entries, yielding 1+2+…+n = **O(n²)** total work.\n\n### PoC (runtime-confirmed on v5.2.0)\n```js\nconst yaml = require('js-yaml');\nfunction buildOmapPayload(n) {\n  let","public_affected_ranges":[">= 5.0.0, <= 5.2.0"]}],"null_published_at":"2026-11-04T10:04:27.862Z","source_updated_at":"2026-07-20T21:18:53.000Z","source_disclosed_at":"2026-07-20T21:18:51.000Z","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":"2026-11-04T02:47:44.783Z"}],"next_cursor":null,"snapshot_revision":"42594"}