CVE-2026-55078

Summary

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 Software

VendorProductVersion RangeStatus
codercoder>= 2.34.0, < 2.34.2affected
codercoder>= 2.33.0, < 2.33.8affected
codercoder>= 2.30.0, < 2.32.7affected
codercoder>= 2.17.0, < 2.29.17affected

Weaknesses

  • CWE-409: CWE-409: Improper Handling of Highly Compressed Data (Data Amplification)
  • CWE-770: CWE-770: Allocation of Resources Without Limits or Throttling

References