CVE-2026-102930 — 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.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Pypa Virtualenv).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Exploitation requires user interaction: tighten email/web filtering and warn affected users.
- Search available logs for exploit probes matching the vulnerability class (integrity), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Pypa | Virtualenv | version < 21.7.12 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.7 | CVSS 4.0 | High | — | — | security-advisories@github.com via NIST National Vulnerability Database |
| 7.7 | CVSS 4.0 | High | — | — | GitHub_M via CVE Program (cve.org) e CISA ADP |
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X (score shown at the top: security-advisories@github.com) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · pypa/virtualenv
- SSVC assessment updated
- Record published
- CVSS changed · 7.7
- Source status changed · → Awaiting Analysis
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
3 on the record
Elsewhere on this site
Related CVEs (same products)
- Medium CVE-2026-102938 virtualenv writes prompt values into pyvenv.cfg without sanitizing line boundaries, allowing configuration injection 16d
- High CVE-2026-102925 virtualenv bash and fish activation scripts execute commands embedded in paths 16d
- High CVE-2026-102937 virtualenv: Command injection via --prompt in activate.bat (batch activator) 16d
- Medium CVE-2026-22702 virtualenv Has TOCTOU Vulnerabilities in Directory Creation Jan 10, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-102930 is "virtualenv: Downloaded seed wheels (pip/setuptools) are not integrity-checked before use", rated High. It affects Virtualenv (Pypa); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.7 describes technical severity. EPSS 0.16% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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