virtualenv: Downloaded seed wheels (pip/setuptools) are not integrity-checked before use
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, download_wheel() accepts pip and setuptools seed wheels fetched for periodic updates or the --download option without checking their bytes against an authoritative digest equivalent to the embedded wheels' BUNDLE_SHA256 verification. A compromised index, stale mirror, or intercepted TLS connection can substitute a different wheel under the requested distribution, version, and filename, after which virtualenv caches and seeds the attacker-controlled wheel into subsequently created environments. The verification applies to the default PyPI path and is intentionally skipped when PIP_INDEX_URL, PIP_EXTRA_INDEX_URL, or PIP_INDEX configures a custom index that may legitimately publish rebuilt wheels. This issue is fixed in version 21.7.12.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-102930
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 5 Nov 2026, 01:28 UTC · Revision 1
Source evidence
virtualenv: Downloaded seed wheels (pip/setuptools) are not integrity-checked before use
core-osv · Original sourcePublished 29 Sept 2026, 20:53 UTC
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, download_wheel() accepts pip and setuptools seed wheels fetched for periodic updates or the --download option without checking their bytes against an authoritative digest equivalent to the embedded wheels' BUNDLE_SHA256 verification. A compromised index, stale mirror, or intercepted TLS connection can substitute a different wheel under the requested distribution, version, and filename, after which virtualenv caches and seeds the attacker-controlled wheel into subsequently created environments. The verification applies to the default PyPI path and is intentionally skipped when PIP_INDEX_URL, PIP_EXTRA_INDEX_URL, or PIP_INDEX configures a custom index that may legitimately publish rebuilt wheels. This issue is fixed in version 21.7.12.
osv:CVE-2026-102930
Complete source record
{
"id": "a8cace541d108a9e20ca9c6397b27bde06c3be43fa46dd5639c8a499bd7194d0",
"url": "https://osv.dev/vulnerability/CVE-2026-102930",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "virtualenv: Downloaded seed wheels (pip/setuptools) are not integrity-checked before use",
"summary": "virtualenv is a tool for creating isolated virtual python environments. Prior to 21.7.12, download_wheel() accepts pip and setuptools seed wheels fetched for periodic updates or the --download option without checking their bytes against an authoritative digest equivalent to the embedded wheels' BUNDLE_SHA256 verification. A compromised index, stale mirror, or intercepted TLS connection can substitute a different wheel under the requested distribution, version, and filename, after which virtualenv caches and seeds the attacker-controlled wheel into subsequently created environments. The verification applies to the default PyPI path and is intentionally skipped when PIP_INDEX_URL, PIP_EXTRA_INDEX_URL, or PIP_INDEX configures a custom index that may legitimately publish rebuilt wheels. This issue is fixed in version 21.7.12.",
"evidence": "osv:CVE-2026-102930",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2026-102930",
"aliases": [
"BIT-virtualenv-2026-102930",
"CVE-2026-102930",
"GHSA-94p9-xgh2-xp45",
"PYSEC-2026-4011"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/pypa/virtualenv",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "9666b42afc8d6103e765d77958d7bae782f5406e"
},
{
"fixed": "a01ed3e2f239d6ab1fce62c5c7664ccf268fff6d"
}
],
"database_specific": {
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "21.7.12"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "a01ed3e2f239d6ab1fce62c5c7664ccf268fff6d"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
"21.7.11",
"21.7.10",
"21.7.9",
"21.7.8",
"21.7.7",
"21.7.6",
"21.7.5",
"21.7.4",
"21.7.3",
"21.7.2",
"21.7.1",
"21.7.0",
"21.6.1",
"21.6.0",
"21.5.2",
"21.5.1",
"21.5.0",
"21.4.3",
"21.4.2",
"21.4.1",
"21.4.0",
"21.3.3",
"21.3.2",
"21.3.1",
"21.3.0",
"21.2.4",
"21.2.3",
"21.2.2",
"21.2.1",
"21.2.0",
"21.1.0",
"21.0.0",
"20.39.1",
"20.39.0",
"20.38.0",
"20.37.0",
"20.27.3",
"20.27.2",
"20.24.3",
"20.3.0",
"20.0.32",
"20.0.7",
"20.0.0b2",
"20.0.0b1"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-102930.json"
}
}
],
"modified": "2026-10-28T02:30:41.603479971Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102930.json",
"https://github.com/pypa/virtualenv/security/advisories/GHSA-94p9-xgh2-xp45",
"https://nvd.nist.gov/vuln/detail/CVE-2026-102930",
"https://github.com/pypa/virtualenv/commit/a01ed3e2f239d6ab1fce62c5c7664ccf268fff6d",
"https://github.com/pypa/virtualenv/pull/3251"
],
"provider_metadata": {
"cwe_ids": [
"CWE-494"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102930.json"
}
},
"related_cves": [
{
"value": "CVE-2026-102930",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 509072,
"published_at": "2026-09-29T20:53:36.018+00:00"
}