CVE-2026-102938

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.11, PyEnvCfg.write() writes prompt values verbatim to the line-oriented pyvenv.cfg format while PyEnvCfg._read_values() parses the file with str.splitlines() and accepts the last value for duplicate keys. An attacker who influences --prompt, VIRTUALENV_PROMPT, or configuration input can insert a recognized line boundary and additional keys, including home, causing consumers to use an attacker-selected base interpreter or corrupted environment metadata. The security impact requires prompt input from outside the operator's trust boundary; directly supplied prompt content primarily corrupts the operator's own environment. This issue is fixed in version 21.7.11.

CVSS

No CVSS.

References

Link	Resource
https://github.com/pypa/virtualenv/commit/a30f995461043acb6cacbf3a890951563ccf7140
https://github.com/pypa/virtualenv/pull/3247
https://github.com/pypa/virtualenv/releases/tag/21.7.11
https://github.com/pypa/virtualenv/security/advisories/GHSA-9h9j-4vrj-gf7g

Configurations

No configuration.

History

29 Sep 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-29 21:17

Updated : 2026-09-30 20:17

NVD link : CVE-2026-102938

Mitre link : CVE-2026-102938

CVE.ORG link : CVE-2026-102938

JSON object : View

Products Affected

No product.

CWE

CWE-93

Improper Neutralization of CRLF Sequences ('CRLF Injection')

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