CVE-2026-6970 json
authd Denial of Service and Local Privilege Escalation
published 2026-04-27 6 mo ago modified 2026-10-26 13 d ago also GHSA-fg3j-5w9g-hmg7 , GO-2026-5361 , EUVD-2026-25871
- cvss
- 7.3
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.1%
- EPSS 0.1% chance of exploitation in 30 days, percentile 1%
- public exploits
- 0
- none known
Summary
authd prior to version 0.6.4 contains a logic error in primary group ID assignment that can lead to local privilege escalation. When a user's primary group ID (GID) differs from their UID, either because the account was created with authd prior to version 0.5.4 or because the primary group was manually changed via the `authctl group set-gid` command, and the user's identity provider record is updated, authd incorrectly resets the user's primary group ID to their UID upon next login. This causes newly created files and directories to be owned by the wrong group, causing denial of service issues, and potentially granting unintended access to other local users and allowing local privilege escalation.
Patch / fix
- go github.com/canonical/authd 0.6.4
- Canonical authd 0.6.1ubuntu0.1, 0.6.4
- authd Ubuntu 26.04 LTS 0.6.1ubuntu0.1
ubuntu advisories UBUNTU-CVE-2026-6970
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 6 mo ago
Exploit prediction
0.11% chance of exploitation in the next 30 days, higher than 1% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.3 | CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 4.0 | 7.3 | CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/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 |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/canonical/authd | >=0.6.0, <0.6.4 |
0.6.4 |
Affected products
- Canonical authd
Classification
- Weakness
-
- CWE-842 Placement of User into Incorrect Group
References
-
github.com
/canonical/authd/commit/154b428305cb1a7a19c897626fefd09d6dde8b9f
patch, web
-
github.com
/canonical/authd/security/advisories/GHSA-fg3j-5w9g-hmg7
vendor-advisory, web, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-6970
advisory
-
github.com
/canonical/authd
package
Sources
- CVE List CVE-2026-6970
- GitHub Advisory GHSA-fg3j-5w9g-hmg7
- NVD CVE-2026-6970
- OSV GO-2026-5361
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.