{"id":"CVE-2026-102938","state":"PUBLISHED","title":"virtualenv writes prompt values into pyvenv.cfg without sanitizing line boundaries, allowing configuration injection","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.","publishedAt":"2026-09-29T20:58:20.696Z","updatedAt":"2026-09-30T19:53:20.817Z","severity":{"score":5.8,"label":"Medium","version":"4.0","vector":"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","source":"GitHub_M"},"assigner":"GitHub_M","products":["pypa virtualenv"],"affected":[{"vendor":"pypa","product":"virtualenv","versions":[{"version":"< 21.7.11","status":"affected"}]}],"references":["https://github.com/pypa/virtualenv/security/advisories/GHSA-9h9j-4vrj-gf7g","https://github.com/pypa/virtualenv/pull/3247","https://github.com/pypa/virtualenv/commit/a30f995461043acb6cacbf3a890951563ccf7140","https://github.com/pypa/virtualenv/releases/tag/21.7.11"],"weaknesses":["CWE-93"],"ingestedAt":"2026-10-29T20:10:13.529Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/102xxx/CVE-2026-102938.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-102938","state":"PUBLISHED","datePublished":"2026-09-29T20:58:20.696Z","dateUpdated":"2026-09-30T19:53:20.817Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-09-29T20:24:43.340Z"},"containers":{"cna":{"title":"virtualenv writes prompt values into pyvenv.cfg without sanitizing line boundaries, allowing configuration injection","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"pypa","product":"virtualenv","versions":[{"version":"< 21.7.11","status":"affected"}]}],"references":[{"url":"https://github.com/pypa/virtualenv/security/advisories/GHSA-9h9j-4vrj-gf7g","name":"https://github.com/pypa/virtualenv/security/advisories/GHSA-9h9j-4vrj-gf7g","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/pypa/virtualenv/pull/3247","name":"https://github.com/pypa/virtualenv/pull/3247","tags":["x_refsource_MISC"]},{"url":"https://github.com/pypa/virtualenv/commit/a30f995461043acb6cacbf3a890951563ccf7140","name":"https://github.com/pypa/virtualenv/commit/a30f995461043acb6cacbf3a890951563ccf7140","tags":["x_refsource_MISC"]},{"url":"https://github.com/pypa/virtualenv/releases/tag/21.7.11","name":"https://github.com/pypa/virtualenv/releases/tag/21.7.11","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"LOCAL","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"PASSIVE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"LOW","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":5.8,"baseSeverity":"MEDIUM","vectorString":"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","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-93","lang":"en","description":"CWE-93: Improper Neutralization of CRLF Sequences ('CRLF Injection')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-29T20:58:20.696Z"},"source":{"advisory":"GHSA-9h9j-4vrj-gf7g","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-30T19:53:10.688613Z","id":"CVE-2026-102938","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-30T19:53:20.817Z"}}]}}}