CVE-2026-81637: team-alembic ash_authentication · Insufficient Session Expiration
Affects team-alembic ash_authenticationSource CVE Database V5
Not known to be exploited · CVSS 2.3 Low : upgrade to 5.0.0-rc.14 or 4.15.0 when convenient.
Data as of 1 Nov 2026, 22:58 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 49% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.0.0-rc.14, 4.15.0
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 1 Nov 2026.
What to do
Upgrade team-alembic ash_authentication to 5.0.0-rc.14 or 4.15.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| team-alembicash_authentication | Affected
| Fixed in
|
| team-alembicash_authentication | Affected
| Fixed in
|
| team-alembicash_authentication | Affected
| Fixed in– |
Hexash_authenticationpkg:hex/ash_authenticationOther threats | Affected
| Fixed in
|
CPE configurations (1)
cpe:2.3:a:team-alembic:ash_authentication:*:*:*:*:*:*:*:*
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, avoid relying solely on the OAuth2 state value for session security and consider additional session management controls.
Description
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.
References
- github.com/team-alembic/ash_authentication/security/advisories/GHSA-3vcj-gxx8-3p44 (opens in a new tab)
- cna.erlef.org/cves/CVE-2026-81637.html (opens in a new tab)
- osv.dev/vulnerability/EEF-CVE-2026-81637 (opens in a new tab)
- github.com/team-alembic/ash_authentication/commit/c5f589058e04239263f50a1430eb17ea6d5dd1a2 (opens in a new tab)
- github.com/team-alembic/ash_authentication/commit/bd4352303bc9d72d007f6818775267585a4bcc2f (opens in a new tab)
- github.com/team-alembic/ash_authentication/commit/d7f939cd02bd618bcaa304631846fa75ffc419d7 (opens in a new tab)