Stack-based buffer over-read in disasm in nasm 2.16 allows attackers to cause a denial of service (crash).

published 2023-08-22 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-42466

cvss: 5.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 21%
public exploits: 0; none known

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-38668 updated 2026-11-07 cvss 5.5

nasm: stack-based buffer overflow in disasm()

Red Hat Enterprise Linux 6 nasm, nasm-rdoff Red Hat Enterprise Linux 7 nasm, nasm-rdoff
affected: no fix planned “Out of support scope”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-10-03)

Exploit prediction

0.29% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

bugzilla.nasm.us https://bugzilla.nasm.us/show_bug.cgi?id=3392811 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Classification

Weakness

CWE-125 Out-of-bounds Read

References

bugzilla.nasm.us /show_bug.cgi?id=3392811
exploit, issue-tracking

Sources

CVE List CVE-2023-38668
NVD CVE-2023-38668

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