{"id":"CVE-2026-113669","aliases":["GHSA-hhvr-8m24-qqr3"],"title":"ApostropheCMS: Cross-domain session token in URL confers session takeover","summary":"ApostropheCMS: Cross-domain session token in URL confers session takeover","severity":"medium","cvss":5.3,"cwe":["CWE-598"],"vendor":"apostrophe","product":"apostrophe","ecosystem":"npm","affected":["apostrophe < 4.33.0","@apostrophecms/passport-bridge < 1.6.1"],"patched":["apostrophe 4.33.0","@apostrophecms/passport-bridge 1.6.1"],"published":"2026-10-20","updated":"2026-10-20","sourceUpdated":"2026-10-20T18:09:02Z","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-hhvr-8m24-qqr3","references":[{"url":"https://github.com/apostrophecms/apostrophe/security/advisories/GHSA-hhvr-8m24-qqr3"},{"url":"https://github.com/advisories/GHSA-hhvr-8m24-qqr3"},{"url":"https://github.com/apostrophecms/apostrophe/commit/9500b8b0e1d630d5e07fbb5fd2c25ed0943845ce","label":"https://github.com/apostrophecms/apostrophe/commit/9500b8b0e1d630d5e07fbb5fd2c25ed0943845ce"},{"url":"https://github.com/apostrophecms/apostrophe/commit/f84fd41cbf6c22eb8d0008fc9c25df1f7130b350","label":"https://github.com/apostrophecms/apostrophe/commit/f84fd41cbf6c22eb8d0008fc9c25df1f7130b350"},{"url":"https://github.com/apostrophecms/apostrophe/releases/tag/apostrophe@4.33.0","label":"https://github.com/apostrophecms/apostrophe/releases/tag/apostrophe@4.33.0"}],"tags":["ghsa","npm","cve.org"],"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N","cvssSource":"cna","ingestedAt":"2026-10-20T18:14:37.212Z","slug":"CVE-2026-113669","body":"## Overview\n\n**Summary**\nApostrophe's cross-domain session migration emits a single-use session token as a URL query parameter and stores it in the Mongo cache. Any client that presents the token silently adopts the target user's full session (including `passport.user`) with no credentials.\n\n**Details**\n`packages/apostrophe/modules/@apostrophecms/i18n/index.js`:\n- Token generation on cross-host/locale flows (L479–487) and passport-bridge cross-locale redirect (`passport-bridge/index.js` L557–593) places the token in the URL.\n- `acceptCrossDomainSessionToken` (L258–298) reads `?aposCrossDomainSessionToken`, `Object.assign`s the stored session (cookie + `passport.user`) onto `req.session`, then nulls the cache entry under namespace `@apostrophecms/i18n:cross-domain-sessions`.\n- Middleware without `before:` is registered for every URL (express `findModuleMiddlewareAndRoutes` L820–879); verified with `APOS_LOG_ALL_ROUTES=1`.\n\n**PoC**\n```\n# 0) Anonymous baseline: admin-only draft → 403\n# 1) Admin logs in legitimately (token minted into redirect URL):\ncurl -c admin.cookies -X POST -H \"Content-Type: application/json\" \\\n     --data '{\"username\":\"admin\",\"password\":\"adminpassword\",\"session\":true}' \\\n     http://localhost:3100/api/v1/@apostrophecms/login/login\n# 2) Attacker with NO credentials visits the leaked token URL:\ncurl -c atk.cookies \"http://localhost:3100/?aposCrossDomainSessionToken=HUNTING_TOKEN\"\n#    → 302 Location: / ; attacker now holds a vulnlab.sid SID cookie\n# 3) Attacker reads admin-only content via adopted session:\ncurl -b atk.cookies \".../api/v1/@apostrophecms/page/d576242ve1dkzb12jiiabujd:en:draft\"\n#    → 200  adopted-session read -> Secret Private Page | secretData = TOP-SECRET-VALUE-abc123\n# 4) Cache entry consumed (single-use): {\"value\":null}\n```\n\n**Impact**\nSession hijack / account takeover of the migrated user for anyone who obtains the token, inheriting all the account's privileges. Exposure is realistic precisely because the token is in URLs: server/proxy/browser-access logs, browser history, and the Referer header when the destination host differs from the source (the intended use case). Single-use limits but does not remove the window.\n\n**Remediation** — Deliver the token via a short-lived HttpOnly signed SameSite cookie rather than a query parameter; bind consumption to the exact source/destination host pair, expire in seconds, and never log it.\n\n## Affected packages\n\n- `apostrophe < 4.33.0`\n- `@apostrophecms/passport-bridge < 1.6.1`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `apostrophe 4.33.0`\n- `@apostrophecms/passport-bridge 1.6.1`","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}