CVE-2026-86688
- Source
- https://cve.org/CVERecord?id=CVE-2026-86688
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-86688.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-86688
- Aliases
-
- EEF-CVE-2026-86688
- GHSA-v577-944g-7h3x
- Published
- 2026-09-17T21:58:00Z
- Modified
- 2026-09-20T11:30:32Z
- Severity
-
- 7.4 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N CVSS Calculator
- Summary
- Session id is not renewed on authentication in ash_authentication, allowing session fixation
- Details
-
Session Fixation vulnerability in team-alembic ash_authentication allows an attacker who can plant a session identifier in a victim's browser to hold an authenticated session once that victim signs in.
AshAuthentication.Plug.Helpers.store_in_session/2 writes the authenticated subject into the existing session with Plug.Conn.put_session/3 and never calls Plug.Conn.configure_session(renew: true), so the identifier the visitor arrived with carries into their authenticated session. Every authentication event reaches this one function: the default success/4 injected by AshAuthentication.Phoenix.Controller.using/1, the AuthController emitted by mix ash_authentication_phoenix.install, and remember-me auto-login. AshAuthentication.Phoenix.Plug.store_in_session/2 is a defdelegate to it. Logout does not close the window either, because clear_session/2 ends with Plug.Conn.clear_session/1, which clears session contents but leaves the identifier intact, so a planted identifier survives a logout-then-login cycle.
This issue affects ash_authentication: from 0.2.0 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-384" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86688.json", "unresolved_ranges": [ { "extracted_events": [ { "introduced": "a939dde9b917c072cdf10c4b0913a9886a4b0231" }, { "fixed": "*" } ], "source": "AFFECTED_FIELD" } ] }- References
-
- https://cna.erlef.org/cves/CVE-2026-86688.html
- https://github.com
- https://osv.dev/vulnerability/EEF-CVE-2026-86688
- https://repo.hex.pm
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86688.json
- https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-v577-944g-7h3x
- https://nvd.nist.gov/vuln/detail/CVE-2026-86688
- https://github.com/team-alembic/ash_authentication/commit/3e1d452cbf1564e87f5f97be882b66fe25af7cfa
- https://github.com/team-alembic/ash_authentication/commit/872db454405ecad4fcdabd9ff3d8755d1d6a69ae
- https://github.com/team-alembic/ash_authentication/commit/a939dde9b917c072cdf10c4b0913a9886a4b0231
- 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": "0.2.0" }, { "fixed": "4.15.0" }, { "introduced": "5.0.0-rc.0" }, { "fixed": "5.0.0-rc.14" } ], "source": [ "DESCRIPTION", "REFERENCES" ] }