What is CVE-2025-9556?

CVE-2025-9556 is a critical-severity vulnerability in Langchaingo, classified under CWE-200 EXPOSURE OF SENSITIVE INFORMATION TO AN UNAUTHORIZED ACTOR. CVSS score: 9.8/10. Published 2025-09-12.

How severe is CVE-2025-9556?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2025-9556 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Langchaingo

CVE-2025-9556

Langchaingo supports the use of jinja2 syntax when parsing prompts, which is in turn parsed using the gonja library v1.5.3. Gonja supports include and extends syntax to read files, which leads to a server side template injection vulnerabi…

EPSS: 0.007 (47.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Langchaingo — versions 0.1.14

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-9556?: CVE-2025-9556 is a critical-severity vulnerability in Langchaingo, classified under CWE-200 EXPOSURE OF SENSITIVE INFORMATION TO AN UNAUTHORIZED ACTOR. CVSS score: 9.8/10. Published 2025-09-12.
How severe is CVE-2025-9556?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2025-9556 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.