pybars4 through 0.9.13 Code Injection via Bracketed Path Segments (up9inc pybars4)

CVE-2026-119717

CRITICAL 9.2

At a glance

Source: NVD
State: PUBLISHED
Published: 2026-10-30 15:16 UTC
Updated: 2026-10-30 18:36 UTC
Assigner: VulnCheck
NVD status: Deferred

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Description

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.

Weaknesses (CWE)

CWE-94 — Improper Control of Generation of Code

References

Scores

Version	Score	Vector	Scored by
CVSS 4.0	CRITICAL 9.2	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	VulnCheck
CVSS 3.1	HIGH 8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H	VulnCheck
CVSS 4.0	CRITICAL 9.2	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/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	NVD · disclosure@vulncheck.com (Secondary)
CVSS 3.1	HIGH 8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H	NVD · disclosure@vulncheck.com (Secondary)

European references

ENISA EUVD · EUVD-2026-114122
GCVE · GCVE-0-2026-119717

Affected products

Product	Versions
up9inc · pybars4	affected 0 ≤ 0.9.13

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD

💣 pybars4 through 0.9.13 Code Injection via Bracketed Path Segments (up9inc pybars4)