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OpenAdvisories
Medium · 6.5 CVE-2026-55078 EUVD-2026-42131GHSA-2mg2-p7r7-g27fGO-2026-5916

Coder: Zip upload decompression lacks aggregate size limit, enabling denial of service

Published Jul 7, 2026 · Updated Jul 8, 2026 · Assigned by GitHub_M

Description

Coder allows organizations to provision remote development environments via Terraform. Starting in version 2.17.0 and prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, `POST /api/v2/files` converts zip uploads to tar in memory via `CreateTarFromZip`, which enforced a per-entry size limit but no aggregate limit on total decompressed output, writing to an unbounded in-memory buffer. Exploitation requires authenticated file-upload access and the impact is limited to availability (denial of service). The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 adds a metadata preflight check that sums projected entry sizes and a streaming writer that enforces the aggregate limit during decompression. As a workaround, restrict file-upload permissions to trusted users or place a reverse proxy with request-body size limits in front of `coderd`.

Affected products

VendorProductAffectedFixed
coder coder >= 2.34.0, < 2.34.2, >= 2.33.0, < 2.33.8, >= 2.30.0, < 2.32.7, >= 2.17.0, < 2.29.17 —

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
openSUSE Leap 16.0 govulncheck-vulndb 0.0.20260723T184607-160000.1.1 openSUSE-SU-2026:21483-1

Affected packages

EcosystemPackageAffectedFixedRecord
Go github.com/coder/coder all versions — GO-2026-5916
Go github.com/coder/coder/v2 >= 2.34.0, < 2.34.2 2.34.2 GHSA-2mg2-p7r7-g27f
Go github.com/coder/coder/v2 >= 2.33.0, < 2.33.8 2.33.8 GHSA-2mg2-p7r7-g27f
Go github.com/coder/coder/v2 >= 2.30.0, < 2.32.7 2.32.7 GHSA-2mg2-p7r7-g27f
Go github.com/coder/coder/v2 >= 2.17.0, < 2.29.17 2.29.17 GHSA-2mg2-p7r7-g27f
Go github.com/coder/coder/v2 >= 2.17.0, < 2.29.17 · >= 2.30.0, < 2.32.7 · >= 2.33.0, < 2.33.8 · >= 2.34.0, < 2.34.2 2.29.17, 2.32.7, 2.33.8, 2.34.2 GO-2026-5916

Advisories 1

References