CVE-2026-119717: up9inc pybars4 · Code Injection
Affects up9inc pybars4Source CVE Database V5
Not known to be exploited · CVSS 9.2 Critical.
Data as of 30 Oct 2026, 16:17 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 9.2 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 8.1 |
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 30 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| up9incpybars4 | Affected
| Fixed in– |
PyPIpybars4pkg:pypi/pybars4Other threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until a fix is available, avoid processing untrusted Handlebars templates or implement strict input validation and escaping to prevent injection of unescaped bracketed path segments.
Description
pybars4 versions up to 0.9.13 contain a critical code injection vulnerability in the pybars/_compiler.py component. This flaw allows attackers to execute arbitrary Python code by supplying crafted Handlebars templates with unescaped bracketed path segments. The vulnerability arises because attackers can break out of the generated resolve() string literal, leading to code execution within the application process.
References
- github.com/vladko312/advisories/blob/702e98db9642ece70d9e2150076d8014ffec2db3/pybars3.md (opens in a new tab)
- github.com/up9inc/pybars4/blob/0.9.13/pybars/_compiler.py (opens in a new tab)
- github.com/up9inc/pybars4 (opens in a new tab)
- vulncheck.com/advisories/pybars4-through-0.9.13-code-injection-via-bracketed-path-segments (opens in a new tab)