Marked allows Regular Expression Denial of Service (ReDoS) attacks

Description

Marked prior to version 0.3.17 is vulnerable to a Regular Expression Denial of Service (ReDoS) attack due to catastrophic backtracking in several regular expressions used for parsing HTML tags and markdown links. An attacker can exploit this vulnerability by providing specially crafted markdown input, such as deeply nested or repetitively structured brackets or tag attributes, which cause the parser to hang and lead to a Denial of Service.

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Browse source ↗
Published (advisory)
2025-05-23 15:31:16 UTC
Updated
2025-05-27 15:03:48 UTC
GitHub reviewed
2025-05-27 15:03:47 UTC
NVD published
2025-05-23

EPSS Score

Score Percentile
0.77% 73.51%

CVSS Scores

Base score Version Severity Vector
6.9 4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:L)
Limited availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.

Identifiers

CWEs

CWE id Name
CWE-1333 Inefficient Regular Expression Complexity

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
npm marked < 0.3.17 0.3.17

References

cvelogic Threat Intelligence