CVE-2026-55078Medium· 6.5▾ SunlitCoder: Zip upload decompression lacks aggregate size limit, enabling denial of service
▾ Sunlit zone — Low / medium · no exploitation signal
impact 35.8 · likelihood 0.1 · exploitation 0
Need a working PoC? Pro members can cast a request and our team develops one — it lands right here.
Exploit-prediction probability, daily snapshots since Jul 8.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via GHSA
0.6%
0.6% → 0.6%
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.
Note: Exploitation requires authenticated file-upload access and the impact is limited to availability (denial of service).
An authenticated user could upload a zip within the 100 MiB upload limit but containing many highly compressible entries whose decompressed size exhausted memory, crashing coderd before any RBAC check. Repeated requests could keep the service unavailable. This is a denial of service; it does not allow data disclosure or code execution.
The fix adds a metadata preflight check that sums projected entry sizes and a streaming writer that enforces the aggregate limit during decompression.
The fix was backported to all supported release lines:
Restrict file-upload permissions to trusted users or place a reverse proxy with request-body size limits in front of coderd.
Coder would like to thank Anthropic's Security Team (ANT-2026-22438) for independently disclosing this issue!
github.com/coder/coder/v2 >= 2.34.0, < 2.34.2github.com/coder/coder/v2 >= 2.33.0, < 2.33.8github.com/coder/coder/v2 >= 2.30.0, < 2.32.7github.com/coder/coder/v2 >= 2.17.0, < 2.29.17Upgrade to a patched release:
github.com/coder/coder/v2 2.34.2github.com/coder/coder/v2 2.33.8github.com/coder/coder/v2 2.32.7github.com/coder/coder/v2 2.29.17Connected by shared product, vendor, weakness, or advisory.
CVE-2026-55434Medium· 6.5Coder vulnerable to denial of service via unbounded request body in AI Bridge provider endpoints
CVE-2024-27918High· 8.2Coder's OIDC authentication allows email with partially matching domain to register
GHSA-8fxq-53rx-ph5fLow· 3.7Coder: Login endpoint user enumeration via timing-defense placeholder in password comparison
GHSA-h58c-xccx-75m3Low· 3.4Coder: Stored HTML injection via unescaped ApplicationName and LogoURL appearance settings
GHSA-qrwj-vh9x-gw5vHigh· 8.3Coder's workspace agent API insecure redirect handling allowed cross-agent file read and write
CVE-2026-55076High· 7.4Coder's OIDC email_verified type coercion bypass enables account takeover via unverified email linking