CVE-2023-24824 | Quadratic complexity may lead to a denial of service in cmark-gfm

Exp

cmark-gfm is GitHub's fork of cmark, a CommonMark parsing and rendering library and program in C. A polynomial time complexity issue in cmark-gfm may lead to unbounded resource exhaustion and subsequent denial of service. This CVE covers quadratic complexity issues when parsing text which leads with either large numbers of `>` or `-` characters. This issue has been addressed in version 0.29.0.gfm.10. Users are advised to upgrade. Users unable to upgrade should validate that their input comes from trusted sources.

Published: 2023-03-31 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-24824 is rated Exploit Available (57.6/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.03%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2023-24824

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-24824

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.28% 1.03% +0.74%
2 2025-11-21 0.65% 0.28% -0.37%
3 2025-11-18 — 0.65% —

Full EPSS history (24 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-24824

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 3.9 1.4 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2023-24824

OS Trackers for CVE-2023-24824

vendor priority summary link
debian not yet assigned CVE-2023-24824 not yet assigned priority: Debian including 4 source packages (cmark-gfm, python-cmarkgfm, r-cran-commonmark, ruby-commonmarker), 20 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 12, open 8. https://security-tracker.debian.org/tracker/CVE-2023-24824
redhat medium — https://access.redhat.com/security/cve/CVE-2023-24824
ubuntu medium CVE-2023-24824 medium priority: Ubuntu including 2 source packages (cmark, cmark-gfm), 26 status rows across 13 suites (bionic, focal, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 12, needs-triage 6, not-affected 6, DNE 1, released 1. https://ubuntu.com/security/CVE-2023-24824

Affected software / configurations for CVE-2023-24824

Vendor Product Version Raw CPE
github cmark-gfm < 0.29.0.gfm.10. cpe:2.3:a:github:cmark-gfm:*:*:*:*:*:*:*:*

References for CVE-2023-24824

cvelogic Threat Intelligence