CVE-2026-81632 — Single-use sign-in token placed in a redirect query string in AshAuthenticationPhoenix
Use of HTTP Request With Sensitive Query String vulnerability in team-alembic AshAuthenticationPhoenix allows someone able to read access logs, proxy logs or browser history to recover a single-use sign-in token and authenticate as its owner. After a successful password sign-in, AshAuthentication.Phoenix.Components.Password.SignInForm builds the sign_in_with_token path with the freshly issued user.__metadata__.token as a query parameter and redirects the browser to it with a GET. The token therefore travels in the request line, where web servers, reverse proxies, request telemetry and the browser's own history record it, all of which outlive the request and are ordinarily less protected than session storage. The redirect destination is restricted to a local path, so this is not an open redirect; the exposure is the retention of a live credential. This issue affects ash_authentication_phoenix: from 1.7.0 before 2.17.4 and from 3.0.0-rc.0 before 3.0.0-rc.11; ash_authentication: from 3.10.5 before 4.15.0 and from 5.0.0-rc.0 before 5.0.0-rc.14.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+2
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Team-alembic Ash Authentication, Team-alembic Ash Authentication Phoenix).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Team-alembic | Ash Authentication | ≥ 3.10.5 and < 4.15.0≥ 5.0.0-rc.0 and < 5.0.0-rc.14≥ eca8cadea0f1595ed2c10a0c177b1da9aa9e5269 | Vulnerable | CVE Program (cve.org) e CISA ADP |
| Team-alembic | Ash Authentication Phoenix | ≥ 1.7.0 and < 2.17.4≥ 3.0.0-rc.0 and < 3.0.0-rc.11≥ 903f3a386e1aba2f7b070187ef6f31215a92bdfd | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.2 | CVSS 4.0 | High | — | — | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db via NIST National Vulnerability Database |
| 7.2 | CVSS 4.0 | High | — | — | EEF via CVE Program (cve.org) e CISA ADP |
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X (score shown at the top: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 15, 2026 → Oct 16, 2026 · 2 reading(s) · max 0.21%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · team-alembic/ash authentication phoenix, team-alembic/ash authentication
- SSVC assessment updated
- Record published
- CVSS changed · 7.2
- Source status changed · → Deferred
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
10 on the record
- github.com/team-alembic/ash_authentication_phoenix/commit/920257d0460b9c7cbb42a8
- github.com/team-alembic/ash_authentication_phoenix/commit/ff5ad8737748afed9cdfde
- github.com/team-alembic/ash_authentication/commit/8d8ddd25c69b669a92a701af74bff4
- github.com/team-alembic/ash_authentication/commit/bbf345c1bb7aa28bce5dd856ac0ed2
- github.com/team-alembic/ash_authentication_phoenix/commit/903f3a386e1aba2f7b0701
- github.com/team-alembic/ash_authentication/security/advisories/GHSA-j726-59hm-r4
- github.com/team-alembic/ash_authentication/commit/eca8cadea0f1595ed2c10a0c177b1d
- cna.erlef.org/cves/CVE-2026-81632.html
- osv.dev/vulnerability/EEF-CVE-2026-81632
- github.com/team-alembic/ash_authentication_phoenix/security/advisories/GHSA-8jh5
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-86688 Session id is not renewed on authentication in ash_authentication, allowing session fixation 29d
- Critical CVE-2026-76949 Remember-me sign-in guard reads a session key that is never written in ash_authentication, allowing session replacement 29d
- Critical CVE-2026-91039 dynamic_oidc identities are not namespaced by connection in ash_authentication, allowing cross-connection account takeover Sep 17, 2026
- Critical CVE-2026-88952 OAuth2 sign-in attached to an existing account without an email comparison in AshAuthentication Sep 17, 2026
- Critical CVE-2026-86533 Revoked session accepted because the session jti is never checked in AshAuthentication and AshAuthentication Phoenix Sep 17, 2026
- Critical CVE-2026-85500 `require_confirmed_with` is not enforced on the action and fails open on an unreadable attribute in AshAuthentication Sep 17, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-81632 is "Single-use sign-in token placed in a redirect query string in AshAuthenticationPhoenix", rated High. It affects Ash Authentication (Team-alembic); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.2 describes technical severity. EPSS 0.21% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
Comments
Moderated technical discussion. Read the community guidelines.
No comments yet.
Sign in or create an account to comment and suggest corrections.