CVE-2026-55432
CVE-2026-55432 — Coder's sub-agent app registration bypasses template port-sharing policy enforcement
Coder allows organizations to provision remote development environments via Terraform. Prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, the `CreateSubAgent` RPC did not validate a requested app sharing level against the template's `MaxPortSharingLevel` before persisting workspace apps, letting a workspace owner exceed the administrator's configured maximum. Exploitation requires the ability to register sub-agent apps in a workspace the attacker controls. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2clamps the sub-agent app sharing level to the template's `MaxPortSharingLevel`. As a workaround, disable wildcard app hostnames (`CODER_WILDCARD_ACCESS_URL`) to block subdomain-based app routing.
Published Updated Sources: cvelistV5, GitHub_M
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
chance of exploitation in 30 days
CVSS base
5.4
MEDIUM
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script all four kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (1)
Products (1)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 5.4 | CVSS 3.1 | MEDIUM | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-862
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1211Exploitation for Defensive Evasion
- T1542.002Pre-OS Boot: Component Firmware
- T1556Modify Authentication Process
References
6 on the record
- github.com/coder/coder/security/advisories/GHSA-x9qq-2qh5-8rxf
x_refsource_CONFIRM
- github.com/coder/coder/pull/26061
x_refsource_MISC
- github.com/coder/coder/releases/tag/v2.29.17
x_refsource_MISC
- github.com/coder/coder/releases/tag/v2.32.7
x_refsource_MISC
- github.com/coder/coder/releases/tag/v2.33.8
x_refsource_MISC
- github.com/coder/coder/releases/tag/v2.34.2
x_refsource_MISC
Elsewhere on this site
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 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.