Vulnerability · Published Feb 9, 2026 · Assigned by VulDB
CVE-2026-2240janet-lang janet compile.c janetc_pop_funcdef out-of-bounds
Low 3.3
In plain English
A low-severity out-of-bounds read in janet from janet-lang. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities).
Official description
A vulnerability has been found in janet-lang janet up to 1.40.1. The impacted element is the function janetc_pop_funcdef of the file src/core/compile.c. Such manipulation leads to out-of-bounds read. The attack must be carried out locally. The exploit has been disclosed to the public and may be used. The name of the patch is 4dd08a4cdef5b1c42d9a2c19fc24412e97ef51d5. A patch should be applied to remediate this issue.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| janet-lang | janet | 1.40.01.40.1 |
Weakness: CWE-125, CWE-119 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C
References
- VDB-344979 | janet-lang janet compile.c janetc_pop_funcdef out-of-bounds vdb-entry, technical-description
- VDB-344979 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
- Submit #753155 | janet-lang janet 883dde4 Heap-based Buffer Overflow third-party-advisory
- https://github.com/janet-lang/janet/issues/1702 issue-tracking
- https://github.com/janet-lang/janet/issues/1702#issuecomment-3790473369 issue-tracking
- https://github.com/oneafter/0123/blob/main/ja4/repro exploit
- https://github.com/janet-lang/janet/commit/4dd08a4cdef5b1c42d9a2c19fc24412e97ef51d5 patch
- https://github.com/janet-lang/janet/ product