virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, virtualenv's ScriptMakerCustom and pip pass an incompletely quoted interpreter path to distlib ScriptMaker when generating POSIX console scripts. When the path contains a space or produces a shebang longer than 127 bytes, distlib emits a /bin/sh wrapper whose double-quoted interpreter path still expands command substitutions and backticks. An attacker who influences the environment destination can therefore execute commands with the user's privileges when the user later runs a generated launcher; environment creation and activation do not trigger the command. Existing launchers are not repaired by upgrading virtualenv alone and must be regenerated, while a later independent pip installation or upgrade can reintroduce an affected launcher because pip's vendored distlib is unchanged. The virtualenv fix is released in version 21.14.9.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 4
- StatusAwaiting Analysis → PublishedNVD modified 2026-10-23 02:03
- StatusPublished → Awaiting AnalysisNVD modified 2026-10-22 16:47
- StatusReceived → PublishedNVD modified 2026-10-20 19:48
- First seenCVSS 7.8NVD modified 2026-10-20 20:17
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 5
- https://github.com/pypa/virtualenv/commit/2519941bed33ee0d3ac99277f67913e439e476a9
- https://github.com/pypa/virtualenv/pull/3417
- https://github.com/pypa/virtualenv/releases/tag/21.14.9
- https://github.com/pypa/virtualenv/security/advisories/GHSA-c978-59m8-c77v
- https://github.com/pypa/virtualenv/security/advisories/GHSA-c978-59m8-c77v