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.
Does this matter?
Lower severity and a low EPSS score (0.29%). Track it; it rarely justifies an emergency change on its own.
Description
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
- 5.6 MEDIUMCVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:A/VC:N/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/M
- EPSS
- 0.29% probability · 22th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-36
- Affected
- pypa/pip
- Source
- cna@python.org
References
- https://github.com/pypa/pip/pull/14110Issue Tracking, Patch
- https://mail.python.org/archives/list/security-announce@python.org/thread/L2BNQGGVQCEV7DROOORQ7WFKKFF2OOQX/Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2026/07/29/7Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.