{"id":"CVE-2026-55078","state":"PUBLISHED","title":"Coder: Zip upload decompression lacks aggregate size limit, enabling denial of service","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`.","publishedAt":"2026-07-07T22:47:07.079Z","updatedAt":"2026-07-08T13:55:16.017Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["coder coder"],"affected":[{"vendor":"coder","product":"coder","versions":[{"version":">= 2.34.0, < 2.34.2","status":"affected"},{"version":">= 2.33.0, < 2.33.8","status":"affected"},{"version":">= 2.30.0, < 2.32.7","status":"affected"},{"version":">= 2.17.0, < 2.29.17","status":"affected"}]}],"references":["https://github.com/coder/coder/security/advisories/GHSA-2mg2-p7r7-g27f","https://github.com/coder/coder/pull/25877","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"],"weaknesses":["CWE-409","CWE-770"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/55xxx/CVE-2026-55078.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-55078","state":"PUBLISHED","datePublished":"2026-07-07T22:47:07.079Z","dateUpdated":"2026-07-08T13:55:16.017Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-16T14:33:35.711Z"},"containers":{"cna":{"title":"Coder: Zip upload decompression lacks aggregate size limit, enabling denial of service","descriptions":[{"lang":"en","value":"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":[{"vendor":"coder","product":"coder","versions":[{"version":">= 2.34.0, < 2.34.2","status":"affected"},{"version":">= 2.33.0, < 2.33.8","status":"affected"},{"version":">= 2.30.0, < 2.32.7","status":"affected"},{"version":">= 2.17.0, < 2.29.17","status":"affected"}]}],"references":[{"url":"https://github.com/coder/coder/security/advisories/GHSA-2mg2-p7r7-g27f","name":"https://github.com/coder/coder/security/advisories/GHSA-2mg2-p7r7-g27f","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/coder/coder/pull/25877","name":"https://github.com/coder/coder/pull/25877","tags":["x_refsource_MISC"]},{"url":"https://github.com/coder/coder/releases/tag/v2.29.17","name":"https://github.com/coder/coder/releases/tag/v2.29.17","tags":["x_refsource_MISC"]},{"url":"https://github.com/coder/coder/releases/tag/v2.32.7","name":"https://github.com/coder/coder/releases/tag/v2.32.7","tags":["x_refsource_MISC"]},{"url":"https://github.com/coder/coder/releases/tag/v2.33.8","name":"https://github.com/coder/coder/releases/tag/v2.33.8","tags":["x_refsource_MISC"]},{"url":"https://github.com/coder/coder/releases/tag/v2.34.2","name":"https://github.com/coder/coder/releases/tag/v2.34.2","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-409","lang":"en","description":"CWE-409: Improper Handling of Highly Compressed Data (Data Amplification)","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-770","lang":"en","description":"CWE-770: Allocation of Resources Without Limits or Throttling","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-07T22:47:07.079Z"},"source":{"advisory":"GHSA-2mg2-p7r7-g27f","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-08T13:54:48.796364Z","id":"CVE-2026-55078","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-08T13:55:16.017Z"}}]}}}