CVE-2026-3386
Published: 01 March 2026
Summary
CVE-2026-3386 is a low-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Wren Wren. Its CVSS base score is 3.3 (Low).
Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 7.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
Threat & Defense at a Glance
Threat & Defense Details
Likely Mitigating ControlsAI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Ongoing control assessments and code testing (static/dynamic analysis, fuzzing) surface memory buffer restriction failures, which are then remediated before release.
Managed runtimes used by platform-independent applications (e.g., JVM, CLR) enforce memory safety, preventing most buffer overflows that require direct memory manipulation.
Memory protections (e.g., W^X, ASLR) make exploitation of buffer-boundary violations far harder to turn into code execution.
Detects exploitation attempts that produce memory corruption, crashes, or anomalous behavior.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
OOB read in local Wren VM/compiler enables application crash/DoS via direct exploitation of memory bounds flaw (T1499.004).
NVD Description
A flaw has been found in wren-lang wren up to 0.4.0. Affected by this vulnerability is the function emitOp of the file src/vm/wren_compiler.c. This manipulation causes out-of-bounds read. It is possible to launch the attack on the local host. The…
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exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.
Deeper analysisAI
CVE-2026-3386 is an out-of-bounds read vulnerability in the Wren programming language virtual machine, specifically affecting versions up to 0.4.0 of the wren-lang/wren project. The flaw resides in the emitOp function within the file src/vm/wren_compiler.c, which can be triggered to read data beyond allocated memory bounds. This issue is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) and CWE-125 (Out-of-bounds Read), with a CVSS v3.1 base score of 3.3 indicating low severity.
Exploitation requires local access to the host (AV:L), low privileges (PR:L), and low attack complexity (AC:L) with no user interaction needed (UI:N). An attacker with these conditions can launch the attack locally, potentially causing a denial of service due to the low-impact availability disruption (A:L), while confidentiality and integrity remain unaffected (C:N/I:N) within the unchanged scope (S:U).
References indicate that an exploit has been publicly disclosed at https://github.com/oneafter/0122/blob/main/i1219/repro, and the project was notified early via GitHub issue #1219 at https://github.com/wren-lang/wren/issues/1219, but has not yet responded. No patches or official mitigations are mentioned in the available advisories from sources like VulDB (https://vuldb.com/?ctiid.348272 and https://vuldb.com/?id.348272). Practitioners should monitor the Wren repository at https://github.com/wren-lang/wren/ for updates and avoid using affected versions in local environments.
Details
- CWE(s)