pybars3 through 0.9.7 Code Injection via Bracketed Path Segments
Affects pybars3 up to and including 0.9.7 when templates use the [...] segment literal syntax. No fix is provided, and CVSS rates it 9.2 critical.
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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? →
- Unclear
- 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
Summary
pybars3 through 0.9.7 contains a code injection vulnerability in pybars/_compiler.py that allows template authors to execute Python code via unescaped bracketed path segments. Attackers can supply Handlebars templates with crafted segments in helper or block arguments to break out of string literals and execute Python in the application process.
Timeline
- CVE published
- First seen by cve.now
- Posted on X by cve.now
Affected versions
- wbond pybars3
through 0.9.7
References 5
GitHub · wbond/pybars3
GitHub · vladko312/advisories
Questions about CVE-2026-119716
What does this mean?
The [...] bracketed path syntax does not escape certain special characters before they are inserted into generated code. This lets a template string run arbitrary code in the context of the Python application.Source: github.com
Am I affected, and how do I check?
pybars3 through version 0.9.7 is affected. To check an installed version, run pip show pybars3 or pip freeze. The issue applies to templates that use the [...] segment literal syntax.Source: github.com
What should I do about it?
The checked sources list no fixed version, so there is no upgrade target yet. Check the project for a newer release before relying on an update.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 states that no fix is provided for pybars3. The only workaround in the sources is to use a WAF or filtering to block code execution payloads.Source: github.com