by Kastro
Paper/Archive/CVE-2026-119717

CVE-2026-119717

up9inc pybars4 — pybars4 through 0.9.13 Code Injection via Bracketed Path Segments

CVSS 9.2
critical.is priorityof 100
28
CVSS 9.2 (CNA)9.2 / 10 × 3027.6Not in CISA KEV+300.0No EPSS score.000 × 200.0No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
pybars4≤ 0.9.13–CNA

Scores by source

VulnCheck (CNA)9.2CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
VulnCheck (CNA)8.1CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

writeupgithub.com/vladko312/advisories/blob/702e98db9642ece70d9e2150076d8014ffec2db3/pybars3.mdwriteupgithub.com/up9inc/pybars4/blob/0.9.13/pybars/_compiler.py#L153-L154refgithub.com/up9inc/pybars4writeupvulncheck.com/advisories/pybars4-through-0.9.13-code-injection-via-bracketed-path-segments