CVE-2026-102937

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, BatchActivator.quote() returns prompt text unchanged before activate.bat inserts it into a cmd.exe set "VAR=value" statement. An attacker who influences --prompt, VIRTUALENV_PROMPT, or the corresponding configuration value can include a double quote that closes the assignment and leaves following cmd.exe operators as executable syntax. When a user activates the generated Windows environment, the injected commands run with that user's privileges. This issue is fixed in version 21.7.12.

CVSS 4.0

7.3CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

EPSS

0.1% chance of exploitation in the next 30 days; higher than 3% of CVEs (scores of 2026-10-25)

CWE

CWE-78

Published

2026-09-29

Modified

2026-10-02

Record from

the NVD, synced 2026-10-19

Packages (OSV)

References

• https://github.com/pypa/virtualenv/commit/d721ff140ce4afdc2a9b76751e4584e25d9fbea6
• https://github.com/pypa/virtualenv/pull/3250
• https://github.com/pypa/virtualenv/releases/tag/21.7.12
• https://github.com/pypa/virtualenv/security/advisories/GHSA-x78j-v8h9-3j2q

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