CVE-2026-42301
pyp2spec is Vulnerable to Code Injection
Description
### Impact pyp2spec was writing PyPI package metadata (e.g. the summary field) into the generated spec file without escaping RPM macro directives. When a packager then runs rpmbuild, those directives get evaluated, so a malicious package can execute arbitrary commands on the build machine. The macro evaluates during spec parsing, not only during the build step. Any rpm tool touching the generated spec triggers execution, `rpmbuild -bs`, `rpmbuild --nobuild`, `rpm -q --specfile`, so the victim doesn't need to commit to a full build before getting compromised. The realistic attack path is typosquatting or targeting a package known to be under Fedora review rather than drive-by publishing. Fedora packagers hold dist-git SSH keys, Koji build credentials, and Bodhi update credentials, so compromise of one packager's workstation enables committing malicious source to dist-git and riding it through the normal build pipeline to end users. ### Patches Patched in 0.14.1. ### Workarounds None
How to fix CVE-2026-42301
To remediate CVE-2026-42301, upgrade the affected package to a fixed version below.
- —upgrade to 0.14.1 or later
Is CVE-2026-42301 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 0.14.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.8 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |