CVE-2026-113732CWE-116CWE-78command-injection

CVE-2026-113732

High · published October 21, 2026

CVSS v3.1
7.8
EPSS
0%
Percentile
10.8
In the wild
Unconfirmed
What it is

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.2, FishActivator inherits ViaTemplateActivator.quote(), which uses POSIX shlex.quote() even though fish interprets backslashes and single quotes differently. An attacker-influenced environment path, --prompt, or VIRTUALENV_PROMPT value containing a backslash before a quote can therefore terminate the generated fish literal and execute command substitution when the user sources activate.fish. This issue is fixed in version 21.14.2.

The record
Technical detail
CVSS v3.1
7.8 · HIGH
Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00211 · 10.8th percentile
Weaknesses
CWE-116 · Improper Encoding or Escaping of Output; CWE-78 · Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Published
2026-10-21T02:19Z
References (3)
https://github.com/pypa/virtualenv/commit/3bddeaf8d02c3ee7f576503efb082f8f494cfcab · [email protected]https://github.com/pypa/virtualenv/releases/tag/21.14.2 · [email protected]https://github.com/pypa/virtualenv/security/advisories/GHSA-c947-3pg5-gm8q · [email protected]
EPSS history
Timeline
  • 22 OCT 03:29Z
    EPSS moved — → 0%
    epss
  • 20 OCT 22:01Z
    virtualenv activate.fish runs commands from a path or prompt with a backslash before a quote
    cvelistv5
  • 20 OCT 22:01Z
    virtualenv activate.fish runs commands from a path or prompt with a backslash before a quote
    cvelistv5