An issue in YASM 1.3.0.86.g9def allows a remote attacker to cause a denial of service via the expand_smacro function in the modules/preproc…

published 2024-01-02 2 y ago modified 2026-06-17 4 mo ago also EUVD-2023-53512

cvss: 5.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 32%
public exploits: 0; none known

An issue in YASM 1.3.0.86.g9def allows a remote attacker to cause a denial of service via the expand_smacro function in the modules/preprocs/nasm/nasm-pp.c component.

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-2023-49555 updated 2025-11-21 cvss 0.0

yasm: remote attacker cause a denial of service via the expand_smacro

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

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: 23 mo ago (2024-11-14)

Exploit prediction

0.38% chance of exploitation in the next 30 days, higher than 32% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/yasm/yasm/issues/248 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
NVD	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CNA	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-400 Uncontrolled Resource Consumption

References

github.com /yasm/yasm/issues/248
exploit, issue-tracking, vendor-advisory

Sources

CVE List CVE-2023-49555
NVD CVE-2023-49555

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