CVE-2026-126403 json
Coder 2.38.0 before 2.38.4 Authorization Bypass via External Agent Credentials Endpoint
published 16d ago modified yesterday also EUVD-2026-125162 , GHSA-9frj-7f83-x984
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository coder/coder. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 28%
- public exploits
- 0
- none known
Summary
Coder 2.26.0 before 2.29.24, 2.30.0 before 2.34.16, 2.35.0 before 2.36.11, 2.37.0 before 2.37.8, and 2.38.0 before 2.38.4 contains an improper authorization flaw in the external agent credentials endpoint, which returns the workspace agent token to users with only workspace read access rather than ssh permission. Authenticated users with roles such as Template Admin or Organization Admin can use the token to read the owner's private Git SSH key and Git provider OAuth tokens, and impersonate the agent to receive the owner's sessions.
Patch / fix
- coder coder 2.29.24, 2.34.16, 2.36.0, 2.36.11, 2.37.8, 2.38.4
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- yesterday
Exploit prediction
0.35% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-14).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.5 | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N |
| CNA | 4.0 | 8.5 | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/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 |
Affected products
- coder coder
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
-
github.com
/coder/coder/security/advisories/GHSA-9frj-7f83-x984
vendor-advisory, advisory
-
vulncheck.com
/advisories/coder-2.38.0-before-2.38.4-authorization-bypass-via-external-agent-credentials-endpoint
third-party-advisory
Sources
- CVE List CVE-2026-126403
- NVD CVE-2026-126403
- Maintainer advisory GHSA-9frj-7f83-x984
Fencer Intel 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.
The maintainers of coder/coder published their own advisory on GitHub. Reviewed sources take precedence over it.