CVE-2026-82685
What it is
Authorization Bypass Through User-Controlled Key vulnerability in team-alembic AshAuthentication allows an authenticated attacker to overwrite and confirm another user's email address, and so take over that account. A confirmation token issued to one user is accepted on any other user's record. AshAuthentication.AddOn.Confirmation.ConfirmChange verifies the token's signature and its act claim, then applies the changes stored against that token to whichever record the changeset targets, never comparing the sub claim against changeset.data. An attacker who registers an account and changes their own email replays the resulting token against a victim's record id, writing in their own address with force_change_attributes/2 and stamping confirmed_at, after which an ordinary password reset yields the account. The library's own confirmation flow is unaffected, because AshAuthentication.AddOn.Confirmation.Actions.confirm/3 resolves sub to a user and targets that record. This issue affects ash_authentication: from 0.5.0 before 4.15.0 and from 5.0.0-rc.0 before 5.0.0-rc.14.
At a glance
- Exploitability
- Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering.
- Exploit odds
- 0.7% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.7% in the next 30 days (EPSS).
- Severity: 7.6 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.7% · EPSS, next 30 days
- Weakness
- CWE-639 · Insecure direct object reference
- Record status
- Deferred
Attack profile CVSS 4.0 · 7.6
- Attack vector
- Network
- Complexity
- Low
- Attack requirements
- Present
- Privileges needed
- Low
- User interaction
- None
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Raw vector
CVSS:4.0/AV:N/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
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-82685.md and follow it. Check whether this project is affected by CVE-2026-82685. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/team-alembic/ash_authentication/commit/1d4bb00617aecae85c33f2ff5bc7e094c6449a6e
- https://github.com/team-alembic/ash_authentication/commit/2a2396af131ab67e2f445b805fecce8e6ca86c0e
- https://github.com/team-alembic/ash_authentication/commit/d7c15c21d39c009206e010cd67e2d86370fe7a28
- https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-g636-26vf-2w63
References
- https://cna.erlef.org/cves/CVE-2026-82685.html
- https://github.com/team-alembic/ash_authentication/commit/1d4bb00617aecae85c33f2ff5bc7e094c6449a6e
- https://github.com/team-alembic/ash_authentication/commit/2a2396af131ab67e2f445b805fecce8e6ca86c0e
- https://github.com/team-alembic/ash_authentication/commit/d7c15c21d39c009206e010cd67e2d86370fe7a28
- https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-g636-26vf-2w63
- https://osv.dev/vulnerability/EEF-CVE-2026-82685