cmark-gfm before 0.29.0.gfm.6: Autolink Extension DoS
CVE-2022-39209 Published on September 15, 2022

Uncontrolled Resource Consumption in cmark-gfm
cmark-gfm is GitHub's fork of cmark, a CommonMark parsing and rendering library and program in C. In versions prior to 0.29.0.gfm.6 a polynomial time complexity issue in cmark-gfm's autolink extension may lead to unbounded resource exhaustion and subsequent denial of service. Users may verify the patch by running `python3 -c 'print("![l"* 100000 + "\n")' | ./cmark-gfm -e autolink`, which will resource exhaust on unpatched cmark-gfm but render correctly on patched cmark-gfm. This vulnerability has been patched in 0.29.0.gfm.6. Users are advised to upgrade. Users unable to upgrade should disable the use of the autolink extension.

Vendor Advisory Vendor Advisory Vendor Advisory NVD

Vulnerability Analysis

CVE-2022-39209 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
NONE
Integrity Impact:
NONE
Availability Impact:
HIGH

Weakness Type

What is a Resource Exhaustion Vulnerability?

The software does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources.

CVE-2022-39209 has been classified to as a Resource Exhaustion vulnerability or weakness.


Products Associated with CVE-2022-39209

You can be notified by email with stack.watch whenever vulnerabilities like CVE-2022-39209 are published in these products:

github Cmark Gfm
 
Fedora Project Fedora
 
Canonical Ubuntu Linux
 

Affected Versions

github cmark-gfm Version < 0.29.0.gfm.6 is affected by CVE-2022-39209

Exploit Probability

EPSS
1.31%
Percentile
79.82%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.