pywasm3 contains a global buffer overflow which leads to segmentation fault

published 2024-05-06 2 y ago modified 2026-06-17 4 mo ago also GHSA-hh39-vjv8-j337 , PYSEC-2024-309 , EUVD-2024-34714

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.6%; EPSS 0.6% chance of exploitation in 30 days, percentile 50%
public exploits: 0; none known

wasm3 v0.5.0 was discovered to contain a global buffer overflow which leads to segmentation fault via the function "PreserveRegisterIfOccupied" in wasm3/source/m3_compile.c.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: total
Assessed: 2 y ago (2024-05-06)

Exploit prediction

0.63% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/wasm3/wasm3/issues/483 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
OSV	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem	package	affected	fixed in
pypi	pywasm3	<=0.5.0	no fix listed

Affected products

wasm3_project wasm3

Classification

Weakness

CWE-120 Buffer Copy without Checking Size of Input

References

github.com /wasm3/wasm3/issues/483
web, exploit, issue-tracking, vendor-advisory, report
nvd.nist.gov /vuln/detail/CVE-2024-34252
advisory
github.com /pypa/advisory-database/tree/main/vulns/pywasm3/PYSEC-2024-309.yaml
web
github.com /wasm3/pywasm3
package
github.com /wasm3/pywasm3/blob/main/wasm3/m3_compile.c#L420
web
github.com /advisories/GHSA-hh39-vjv8-j337
advisory

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary