CVE-2023-22485

Memory Safety in Github Cmark-Gfm ≤ 0.29.0.gfm.7

Public PoCMemory Safety

Published

24 January 2023

Modified

21 November 2024

CVSS Score v3.1 5.3

Click a component to see what it means

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS Score 0.0072 53th percentile

Risk Priority 45 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-22485 is a medium-severity Out-of-bounds Read (CWE-125) vulnerability in Github Cmark-Gfm. Its CVSS base score is 5.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data Obfuscation (T1001); ranked in the top 47% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

OWASP Top 10 for Web (2025)

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2023-26632

Vulnerability Data

cmark-gfm is GitHub's fork of cmark, a CommonMark parsing and rendering library and program in C. In versions prior 0.29.0.gfm.7, a crafted markdown document can trigger an out-of-bounds read in the `validate_protocol` function. We believe this bug is harmless in…

practice, because the out-of-bounds read accesses `malloc` metadata without causing any visible damage.This vulnerability has been patched in 0.29.0.gfm.7.

CWE(s): CWE-125 CWE-91

Related Threats

MITRE ATT&CK Enterprise Techniques

T1001 Data Obfuscation Command And Control

Adversaries may obfuscate command and control traffic to make it more difficult to detect.

attack.mitre.org →

T1001.002 Steganography Command And Control

Adversaries may use steganographic techniques to hide command and control traffic to make detection efforts more difficult.

attack.mitre.org →

T1003.002 Security Account Manager Credential Access

Adversaries may attempt to extract credential material from the Security Account Manager (SAM) database either through in-memory techniques or through the Windows Registry where the SAM database is stored.

attack.mitre.org →

T1003.003 NTDS Credential Access

Adversaries may attempt to access or create a copy of the Active Directory domain database in order to steal credential information, as well as obtain other information about domain members such as devices, users, and access rights.

attack.mitre.org →

T1003.004 LSA Secrets Credential Access

Adversaries with SYSTEM access to a host may attempt to access Local Security Authority (LSA) secrets, which can contain a variety of different credential materials, such as credentials for service accounts.

attack.mitre.org →

T1003.006 DCSync Credential Access

Adversaries may attempt to access credentials and other sensitive information by abusing a Windows Domain Controller's application programming interface (API)(Citation: Microsoft DRSR Dec 2017) (Citation: Microsoft GetNCCChanges) (Citati…

attack.mitre.org →

Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-48822Shared CWE-125

CVE-2023-42063Shared CWE-125

CVE-2025-21905Shared CWE-125

CVE-2026-43048Shared CWE-125

CVE-2024-27382Shared CWE-125

CVE-2024-5159Shared CWE-125

CVE-2026-4462Shared CWE-125

CVE-2023-32206Shared CWE-125

CVE-2026-53402Shared CWE-125

CVE-2025-6635Shared CWE-125

Affected Assets

github

cmark-gfm

≤ 0.29.0.gfm.7

Mitigating Controls

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

ID.RA-01 partial match

blocks

Vulnerability scanning and recording can discover instances of out-of-bounds reads after code is deployed.

PR.PS-02 partial match

blocks

Routine patching replaces vulnerable code containing out-of-bounds read flaws.

PR.PS-06 partial match

blocks

Secure-development practices such as bounds checking and memory-safe languages directly prevent out-of-bounds reads.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.14 Information transfer partial match

removes

A.5.15 Access control partial match

removes

A.5.16 Identity management partial match

removes

A.5.17 Authentication information partial match

removes

A.5.18 Access rights partial match

removes

A.8.10 Information deletion partial match

removes