Medium severity · published Jul 7, 2026
CVE-2026-55079
Coder's unbounded memory allocation in provisioner file upload allows authenticated denial of service
6.5
CVSS
0.6%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
coder · coder
>= 2.34.0, < 2.34.2; >= 2.33.0, < 2.33.8; >= 2.30.0, < 2.32.7; >= 2.24.0, < 2.29.17 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-55079
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-55079
Issue Tracking
https://github.com/coder/coder/pull/25710
Release Notes
https://github.com/coder/coder/releases/tag/v2.29.17
Release Notes
https://github.com/coder/coder/releases/tag/v2.32.7
Release Notes
https://github.com/coder/coder/releases/tag/v2.33.8
Release Notes
https://github.com/coder/coder/releases/tag/v2.34.2
Patch
https://github.com/coder/coder/security/advisories/GHSA-f962-qm93-mj4c
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