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Fencer Intel
medium 5.3

CVE-2026-115791 json

Prevent shadowing stdlib in gzip/tarfile/zipfile CLI during extraction

published yesterday modified yesterday also EUVD-2026-121328

cvss
5.3
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

When tarfile or zipfile command line interface (CLI) is used to

decompress an archive, a Python script shadowing the stdlib can be

created. Then if an error occurs during decompressing the next file,

the newly created Python script is executed. This is especially true

if the created Python is called traceback.py. The problem is that

Python adds the current directory to sys.path when python -m MODULE is

run, and the archive is also decompressed in the current directory.

The fix removes sys.path[0] in gzip, tarfile and zipfile command line

interface to prevent shadowing standard library modules from extracted

files.

Patch / fix

  • Python Software Foundation CPython 3.16.0

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
2d ago

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 4.0 5.3 CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CNA 4.0 5.3 CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

  • Python Software Foundation CPython

Classification

Weakness
  • CWE-829 Inclusion of Functionality from Untrusted Control Sphere

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.