CVE-2026-102938
virtualenv writes prompt values into pyvenv.cfg without sanitizing line boundaries, allowing configuration injection
- State
- Published
- Severity
- 5.8 Medium
- Published
- Sep 29, 2026
- Updated
- Sep 30, 2026
- Reserved
- Sep 29, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 5.8 Medium | CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N | GitHub_M |
Weaknesses
- CWE-93 Improper Neutralization of CRLF Sequences ('CRLF Injection')
Affected Products
| Product | Versions |
|---|---|
virtualenvpypa |
|
References
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.