pybars4 through 0.9.13 Code Injection via Bracketed Path Segments
Affects pybars4 up to and including 0.9.13 for templates that use the bracketed [...] path segment syntax. No fixed version is listed.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Default setups
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
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.
Timeline
- CVE published
- First seen by cve.now
- Posted on X by cve.now
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- up9inc pybars4
through 0.9.13
References 4
GitHub · vladko312/advisories
GitHub · up9inc/pybars4
Questions about CVE-2026-119717
What does this mean?
Templates in pybars4 that use the bracketed [...] path segment syntax can lead to arbitrary code execution. The code runs in the context of the Python application that renders the template.Source: github.com
Am I affected, and how do I check?
The listed affected range is pybars4 up to and including version 0.9.13, and the template must use the [...] path segment syntax. To check, run pip show pybars4 to see the installed version and search templates for bracketed [...] path segments.Source: github.com
What should I do about it?
No fixed version is listed, so the advisory gives no upgrade target. The only listed mitigation is to use WAF or filtering to block code execution payloads.Source: github.com
Is it being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What if there's no patch?
The vendor has not provided a fix for pybars4. The listed workaround is to use WAF or filtering to block code execution payloads.Source: github.com