CVE-2026-13346

pip would incorrectly handle doubly-encoded package URLs from indexes allowing for files to be installed to arbitrary locations on disk even when installing wheels. This vulnerability requires downloading or installing a package from a malicious package index to succeed, malicious packages alone are not able to exploit this vulnerability. Note that this vulnerability only materially impacts users running `pip download` with the `--only-binary` option as installing source distributions from an untrusted index is already an unsafe operation that executes code during install time.

CVSS 4.0

5.6CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS 3.1

6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

EPSS

0.3% chance of exploitation in the next 30 days; higher than 21% of CVEs (scores of 2026-10-25)

CWE

CWE-36

Published

2026-07-29

Modified

2026-10-24

Record from

the NVD, synced 2026-10-24

Affected

• pypa:pip

Packages (OSV)

References

• https://github.com/pypa/pip/pull/14110
• https://mail.python.org/archives/list/security-announce@python.org/thread/L2BNQGGVQCEV7DROOORQ7WFKKFF2OOQX/
• http://www.openwall.com/lists/oss-security/2026/07/29/7

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