CVE-2026-33155: DeepDiff has Memory Exhaustion DoS through SAFE_TO_IMPORT

March 18, 2026 (updated April 14, 2026)

The pickle unpickler _RestrictedUnpickler validates which classes can be loaded but does not limit their constructor arguments. A few of the types in SAFE_TO_IMPORT have constructors that allocate memory proportional to their input (builtins.bytes, builtins.list, builtins.range). A 40-byte pickle payload can force 10+ GB of memory, which crashes applications that load delta objects or call pickle_load with untrusted data.

References

github.com/advisories/GHSA-54jj-px8x-5w5q
github.com/qlustered/deepdiff/commit/0d07ec21d12b46ef4e489383b363eadc22d990fb
github.com/qlustered/deepdiff/security/advisories/GHSA-54jj-px8x-5w5q
github.com/seperman/deepdiff
nvd.nist.gov/vuln/detail/CVE-2026-33155

Code Behaviors & Features

Detect and mitigate CVE-2026-33155 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Dependency Scanning using SBOM also detects vulnerabilities from proprietary advisories that this site does not include. Learn more about Dependency Scanning using SBOM →