{"items":[{"id":"NVI-00012961","kind":"vulnerability","title":"H3: Unbounded Chunked Cookie Count in Session Cleanup Loop may Lead to Denial of Service","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-q5pr-72pq-83v3","CVE-2026-86250"],"plain_summary":"GitHub lists this reviewed advisory for h3. 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-1e4cb6e748b8ed3b3ab96209dfc056ce"],"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":"2026-09-30T23:46:51.000Z","value":"5.3 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-200cbebaa29dc6162fa2ea8892d65b08"},{"kind":"CVSS","as_of":"2026-09-18T18:17:18.657Z","value":"7.5 HIGH (3.1)","meaning":"disclosure@vulncheck.com severity; no combined Null risk score.","source_id":"sr-1e4cb6e748b8ed3b3ab96209dfc056ce"},{"kind":"CVSS","as_of":"2026-09-18T18:17:18.657Z","value":"8.7 HIGH (4.0)","meaning":"disclosure@vulncheck.com severity; no combined Null risk score.","source_id":"sr-1e4cb6e748b8ed3b3ab96209dfc056ce"}],"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-200cbebaa29dc6162fa2ea8892d65b08","url":"https://github.com/advisories/GHSA-q5pr-72pq-83v3","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-q5pr-72pq-83v3","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T07:22:52.960Z"},{"id":"sr-1e4cb6e748b8ed3b3ab96209dfc056ce","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86250","basis":"official_catalog","notes":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","title":"CVE-2026-86250","publisher":"NIST National Vulnerability Database","observed_at":"2026-11-04T09:59:21.684Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-200cbebaa29dc6162fa2ea8892d65b08"],"technology":"h3","known_exclusions":[],"conditions_summary":"## Summary\n\nThe `setChunkedCookie()` and `deleteChunkedCookie()` functions in h3 trust the chunk count parsed from a user-controlled cookie value (`__chunked__N`) without any upper bound validation. An unauthenticated attacker can send a single request with a crafted cookie header (e.g., `Cookie: h3=__chunked__999999`) to any endpoint using sessions, causing the server to enter an O(n²) loop that hangs the process.\n\n## Details\n\nThe chunked cookie system stores large cookie values by splitting them into numbered chunks. The main cookie stores a sentinel value `__chunked__N` indicating how many chunks exist. When setting a new chunked cookie, the code cleans up any previous chunks that are no longer needed.\n\nThe vulnerability is in `getChunkedCookieCount()` at `src/utils/cookie.ts:244-249`:\n\n```typescript\nfunction getChunkedCookieCount(cookie: string | undefined): number {\n  if (!cookie?.startsWith(CHUNKED_COOKIE)) {\n    return Number.NaN;\n  }\n  return Number.parseInt(cookie.slice(CHUNKED_COOKIE.length));\n  // No upper bound check — attacker controls this value\n}\n```\n\nThis value is consumed without validation in the cleanup loop of `setChunkedCookie()` at `src/utils/cookie.ts:182-190","public_affected_ranges":[">= 2.0.0-beta.4, < 2.0.1-rc.18"]}],"null_published_at":"2026-11-04T10:04:35.918Z","source_updated_at":"2026-09-30T23:46:51.000Z","source_disclosed_at":"2026-03-23T21:44:55.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Source facts changed; compare the preserved prior revision.","null_first_observed_at":"2026-11-01T07:22:52.960Z"},{"id":"NVI-00012961","kind":"vulnerability","title":"H3: Unbounded Chunked Cookie Count in Session Cleanup Loop may Lead to Denial of Service","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-q5pr-72pq-83v3","CVE-2026-86250"],"plain_summary":"GitHub lists this reviewed advisory for h3. 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-200cbebaa29dc6162fa2ea8892d65b08"],"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":"2026-09-30T23:46:51.000Z","value":"5.3 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-200cbebaa29dc6162fa2ea8892d65b08"}],"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-200cbebaa29dc6162fa2ea8892d65b08","url":"https://github.com/advisories/GHSA-q5pr-72pq-83v3","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-q5pr-72pq-83v3","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T07:22:52.960Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-200cbebaa29dc6162fa2ea8892d65b08"],"technology":"h3","known_exclusions":[],"conditions_summary":"## Summary\n\nThe `setChunkedCookie()` and `deleteChunkedCookie()` functions in h3 trust the chunk count parsed from a user-controlled cookie value (`__chunked__N`) without any upper bound validation. An unauthenticated attacker can send a single request with a crafted cookie header (e.g., `Cookie: h3=__chunked__999999`) to any endpoint using sessions, causing the server to enter an O(n²) loop that hangs the process.\n\n## Details\n\nThe chunked cookie system stores large cookie values by splitting them into numbered chunks. The main cookie stores a sentinel value `__chunked__N` indicating how many chunks exist. When setting a new chunked cookie, the code cleans up any previous chunks that are no longer needed.\n\nThe vulnerability is in `getChunkedCookieCount()` at `src/utils/cookie.ts:244-249`:\n\n```typescript\nfunction getChunkedCookieCount(cookie: string | undefined): number {\n  if (!cookie?.startsWith(CHUNKED_COOKIE)) {\n    return Number.NaN;\n  }\n  return Number.parseInt(cookie.slice(CHUNKED_COOKIE.length));\n  // No upper bound check — attacker controls this value\n}\n```\n\nThis value is consumed without validation in the cleanup loop of `setChunkedCookie()` at `src/utils/cookie.ts:182-190","public_affected_ranges":[">= 2.0.0-beta.4, < 2.0.1-rc.18"]}],"null_published_at":"2026-11-01T07:29:12.905Z","source_updated_at":"2026-09-30T23:46:51.000Z","source_disclosed_at":"2026-03-23T21:44:55.000Z","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":"2026-11-01T07:22:52.960Z"}],"next_cursor":null,"snapshot_revision":"42594"}