Buffer overflow in Wren
CVE-2026-2657
A vulnerability has been found in wren-lang wren up to 0.4.0. This impacts the function printError of the file src/vm/wren_compiler.c of the component Error Message Handler. Such manipulation leads to stack-based buffer overflow. An attack has to be approached locally. The exploit has been disclosed to the public and may be used. The project was informed of the problem early through an issue report but has not responded yet.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.002 (10.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 11th percentile — 10.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.002 · change: -0.000
Affected products
- Wren
- Wren-Lang Wren — versions 0.1, 0.2, 0.3
Weakness classification (CWE)
References
- vuldb.com/ (technical-description, VDB Entry, Third Party Advisory, vdb-entry)
- vuldb.com/ (signature, permissions-required, VDB Entry, Third Party Advisory)
- vuldb.com/ (VDB Entry, Third Party Advisory, third-party-advisory)
- github.com/wren-lang/wren/issues/1221 (issue-tracking, Exploit, Vendor Advisory)
- github.com/oneafter/0122/blob/main/i1221/repro (Exploit, exploit)
- github.com/wren-lang/wren/ (Product, product)
Frequently asked questions
- What is CVE-2026-2657?
- CVE-2026-2657 is a low-severity vulnerability in Wren, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 3.3/10. Published 2026-02-18.
- How severe is CVE-2026-2657?
- Low severity. CVSS v3 base score is 3.3 out of 10.