Coder: Workspace agent API insecure redirect handling allowed cross-agent file read and write
Summary
| CVE | CVE-2026-63443 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-15 17:17:23 UTC |
| Updated | 2026-09-30 17:51:36 UTC |
| Description | Coder allows organizations to provision remote development environments via Terraform. Prior to 2.29.19, 2.32.9, 2.33.10, and 2.34.4, agentConn.apiClient() follows redirects while its custom transport accepts the host from the redirected request URL when the port is the workspace agent HTTP API port 4. An authenticated user who controls a modified workspace agent and knows another online agent's UUID can derive the victim's tailnet address and redirect control-plane requests to that agent. HTTP 301, 302, and 303 redirects can redirect read requests, while HTTP 307 and 308 preserve replayable write and process-start requests. The redirected workspace agent file APIs can read or write files as the victim workspace user, and affected versions exposing the workspace agent process API can execute commands after a redirected file write, crossing workspace and tenant boundaries. This issue is fixed in versions 2.29.19, 2.32.9, 2.33.10, and 2.34.4. |
Risk And Classification
Primary CVSS: v3.1 8.3 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L
EPSS: 0.007620000 probability, percentile 0.535840000 (date 2026-09-29)
Problem Types: CWE-863 | CWE-918 | CWE-863 CWE-863: Incorrect Authorization | CWE-918 CWE-918: Server-Side Request Forgery (SSRF)
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 8.3 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L |
| 3.1 | CNA | DECLARED | 8.3 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
LowCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/coder/coder/pull/26611 | [email protected] | github.com | |
| github.com/coder/coder/releases/tag/v2.32.9 | [email protected] | github.com | |
| github.com/coder/coder/commit/2312b67bc52c4e314c18c4b4be5dcf5500c94ad7 | [email protected] | github.com | |
| github.com/coder/coder/pull/26612 | [email protected] | github.com | |
| github.com/coder/coder/pull/26600 | [email protected] | github.com | |
| github.com/coder/coder/commit/eeb2624549ddb85538e493af3e678fdb185a809f | [email protected] | github.com | |
| github.com/coder/coder/security/advisories/GHSA-qrwj-vh9x-gw5v | [email protected] | github.com | |
| github.com/coder/coder/pull/26622 | [email protected] | github.com | |
| github.com/coder/coder/commit/ec3ba84c0002f47dd979c073cde1ab345acbaea5 | [email protected] | github.com | |
| github.com/coder/coder/releases/tag/v2.29.19 | [email protected] | github.com | |
| github.com/coder/coder/commit/f8bdec5add4711650d5bfb6ff93d0cc9d7821c81 | [email protected] | github.com | |
| github.com/coder/coder/commit/812549d671d0f5a0b45adcee860d37b70aaddccd | [email protected] | github.com | |
| github.com/coder/coder/releases/tag/v2.33.10 | [email protected] | github.com | |
| github.com/coder/coder/releases/tag/v2.34.4 | [email protected] | github.com | |
| github.com/coder/coder/pull/26613 | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.