High severity · published Sep 29, 2026
CVE-2026-102937
virtualenv: Command injection via --prompt in activate.bat (batch activator)
7.3
CVSS
0.1%
EPSS
No
On KEV
Description
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 4% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
VI
virtualenv · pypa
< 21.7.12 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-102937
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-102937
x_refsource_CONFIRM
https://github.com/pypa/virtualenv/security/advisories/GHSA-x78j-v8h9-3j2q
x_refsource_MISC
https://github.com/pypa/virtualenv/pull/3250
x_refsource_MISC
https://github.com/pypa/virtualenv/commit/d721ff140ce4afdc2a9b76751e4584e25d9fbea6
x_refsource_MISC
https://github.com/pypa/virtualenv/releases/tag/21.7.12
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