CVE-2026-81637
- Source
- https://cve.org/CVERecord?id=CVE-2026-81637
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-81637.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-81637
- Aliases
-
- EEF-CVE-2026-81637
- GHSA-3vcj-gxx8-3p44
- Published
- 2026-09-17T13:09:06Z
- Modified
- 2026-09-20T11:30:59Z
- Severity
-
- 2.3 (Low) CVSS_V4 - CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N CVSS Calculator
- Summary
- Replayable OAuth2 CSRF state retained after a failed callback in AshAuthentication
- Details
-
Insufficient Session Expiration vulnerability in team-alembic AshAuthentication allows an attacker who obtains a victim's OAuth2 state value to replay the callback and sign that victim into an attacker-controlled account.
AshAuthentication.Strategy.OAuth2.Plug.callback/2 clears the stored session_params through a rebinding step inside its with chain, conn <- delete_session(conn, session_key). Elixir evaluates the else block in the scope enclosing the with, so every failure path (the provider returning ?error=access_denied, an invalid code, a token-exchange error, or a registration or sign-in failure) reaches store_authentication_result/2 holding the original connection and the session entry is never removed. The value the module's own comment describes as protection against a CSRF-related attack is therefore consumed only when authentication succeeds, and survives a cancelled or failed attempt until the next request phase or session expiry.
This issue affects ash_authentication: from 0.6.0 before 4.15.0 and from 5.0.0-rc.0 before 5.0.0-rc.14.
- Database specific
{ "cna_assigner": "EEF", "cwe_ids": [ "CWE-613" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81637.json", "unresolved_ranges": [ { "extracted_events": [ { "introduced": "c5f589058e04239263f50a1430eb17ea6d5dd1a2" }, { "fixed": "*" } ], "source": "AFFECTED_FIELD" } ] }- References
-
- https://cna.erlef.org/cves/CVE-2026-81637.html
- https://github.com
- https://osv.dev/vulnerability/EEF-CVE-2026-81637
- https://repo.hex.pm
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81637.json
- https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-3vcj-gxx8-3p44
- https://nvd.nist.gov/vuln/detail/CVE-2026-81637
- https://github.com/team-alembic/ash_authentication/commit/bd4352303bc9d72d007f6818775267585a4bcc2f
- https://github.com/team-alembic/ash_authentication/commit/c5f589058e04239263f50a1430eb17ea6d5dd1a2
- https://github.com/team-alembic/ash_authentication/commit/d7f939cd02bd618bcaa304631846fa75ffc419d7
- https://github.com/team-alembic/ash_authentication
Affected packages
Git / github.com/team-alembic/ash_authentication
Affected ranges
- Type
- GIT
- Repo
- https://github.com/team-alembic/ash_authentication
- Events
-
IntroducedFixedIntroducedFixedFixedFixedFixed
- Database specific
-
Show details
{ "extracted_events": [ { "introduced": "0.6.0" }, { "fixed": "4.15.0" }, { "introduced": "5.0.0-rc.0" }, { "fixed": "5.0.0-rc.14" } ], "source": [ "DESCRIPTION", "REFERENCES" ] }