Resource exhaustion in Qluster Deepdiff

CVE-2026-33155

DeepDiff is a project focused on Deep Difference and search of any Python data. From version 5.0.0 to before version 8.6.2, 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. This issue has been patched in version 8.6.2.

Vulnerability class: DoS (Denial of Service)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.005 (41.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 41.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-33155: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33155?
CVE-2026-33155 is a high-severity vulnerability in Qluster Deepdiff, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-03-20.
How severe is CVE-2026-33155?
High severity. CVSS v3 base score is 7.5 out of 10.