CVE-2025-6272 wasm3 m3_compile.c MarkSlotAllocated out-of-bounds write
A local attacker can trigger an out-of-bounds write in the wasm3 library, potentially leading to code execution or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-6272?
CVE-2025-6272 is a medium-severity memory corruption vulnerability in wasm3, published on 19 Jun 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A vulnerability has been found in wasm3 0.5.0 and classified as problematic. This vulnerability affects the function MarkSlotAllocated of the file source/m3_compile.c. The manipulation leads to out-of-bounds write. An attack has to be approached locally. The exploit has been disclosed to the public and may be used.
Which versions are affected by CVE-2025-6272?
3 open source packages ship an affected version, including pywasm3. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
pywasm3 PyPI | All versions to 0.5.0 | None |
pywasm3 PyPI | All versions to 0.5.0 | None |
pywasm3 PyPI | All versions to 0.5.0 | None |
Products include Wasm3 Project Wasm3.
How do I fix CVE-2025-6272?
No fix has been published for CVE-2025-6272 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2025-6272 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-6272 exists.
Other vulnerabilities in wasm3
- CVE-2024-34249 pywasm3 contains a heap buffer overflow which leads to segmentation fault
- CVE-2024-27528 pywasm3 has an Invalid Memory Read, Leading to DoS and Potential Code Execution
- CVE-2024-27529 wasm3 uncontrolled memory allocation vulnerability
- CVE-2024-27530 pywasm3 contains a Use-After-Free in ForEachModule
- CVE-2022-28990 Buffer overflow in wasm3
Sources
Also known as GHSA-rrmw-gv85-w824, PYSEC-2025-186.