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.
https://mail.python.org/archives/list/[email protected]/thread/L2BNQGGVQCEV7DROOORQ7WFKKFF2OOQX/
Published: 2026-07-29
Updated: 2026-07-30
Base Score: 4.6
Vector: CVSS2#AV:N/AC:H/Au:M/C:N/I:C/A:N
Severity: Medium
Base Score: 4.2
Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:N
Severity: Medium
Base Score: 5.6
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00347