CVE-2026-119717: up9inc pybars4 (Critical, CVSS 9.2)
- CVSS
- 9.2 Critical (v4.0)
- Exploited in the wild
- Not on CISA’s KEV list
- Public exploit
- None reported in public exploit databases
- Weakness
- CWE-94
- Vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N- Published
- Oct 30, 2026
What it is
pybars4 through 0.9.13 contains a code injection vulnerability in pybars/_compiler.py that allows attackers to execute Python code via unescaped bracketed path segments in Handlebars templates. Attackers can supply a template with a crafted segment in a helper or block argument to break out of the generated resolve() string literal and execute code in the application process.
Description from the National Vulnerability Database.
What to do
Check whether you run up9inc pybars4, then apply the vendor’s fix or mitigation from the advisories below.
Sources: NVD, FIRST EPSS, CISA KEV, and public exploit databases (availability only). ThreatRoundup reports whether public exploit code exists but never links to it: fake proof-of-concepts that infect security researchers are common. This page updates automatically.