CVE-2026-55079
Coder's unbounded memory allocation in provisioner file upload allows authenticated denial of service
- State
- Published
- Severity
- 4.9 Medium
- Published
- Jul 7, 2026
- Updated
- Jul 8, 2026
- Reserved
- Jun 16, 2026
Description
Coder allows organizations to provision remote development environments via Terraform. Starting in version 2.24.0 and prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, `NewDataBuilder` in `provisionersdk/proto/dataupload.go` allocated a byte slice using the client-supplied `FileSize` from a `DataUpload` message without an upper-bound check. Although the DRPC wire limit is 4 MiB, the `FileSize` value itself was unconstrained. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 validates `FileSize` against an upper bound (`MaxFileSize = 100 MiB`) before allocation. As a workaround, restrict access to the provisioner daemon serve endpoint to trusted provisioner daemon service accounts.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 4.9 Medium | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H | GitHub_M |
Weaknesses
- CWE-789 Memory Allocation with Excessive Size Value
Affected Products
| Product | Versions |
|---|---|
codercoder |
|
References
- https://github.com/coder/coder/security/advisories/GHSA-f962-qm93-mj4c
- https://github.com/coder/coder/pull/25710
- https://github.com/coder/coder/releases/tag/v2.29.17
- https://github.com/coder/coder/releases/tag/v2.32.7
- https://github.com/coder/coder/releases/tag/v2.33.8
- https://github.com/coder/coder/releases/tag/v2.34.2
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