CVE-2020-5238

Denial of service in table parsing in cmark-gfm

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

The table extension in GitHub Flavored Markdown before version 0.29.0.gfm.1 takes O(n * n) time to parse certain inputs. An attacker could craft a markdown table which would take an unreasonably long time to process, causing a denial of service. This issue does not affect the upstream cmark project. The issue has been fixed in version 0.29.0.gfm.1.

La extensión de tabla en GitHub Flavored Markdown anterior a la versión 0.29.0.gfm.1 toma un tiempo O(n*n) en analizar determinadas entradas. Un atacante podría crear una tabla de descuento que tomaría un tiempo irrazonablemente largo de procesar, causando una denegación de servicio. Este problema no afecta el proyecto cmark aguas arriba. El problema se ha corregido en la versión 0.29.0.gfm.1

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

Single

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-01-02 CVE Reserved
2020-07-01 CVE Published
2023-12-05 EPSS Updated
2024-08-04 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-20: Improper Input Validation

CAPEC

References (7)

URL	Tag	Source
https://github.com/github/cmark-gfm/security/advisories/GHSA-7gc6-9qr5-hc85	Third Party Advisory

URL	Date	SRC

URL	Date	SRC
https://github.com/github/cmark-gfm/commit/85d895289c5ab67f988ca659493a64abb5fec7b4	2023-11-07

URL	Date	SRC
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TCDHBTUFIOYRIS5HAS6PZNBNMB7IOAX3	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WMQFOQQCWOAMQ4I2XIVCVOXXIJ75HDCW	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZGJH2A4VAV54X6NSCNNGSEIGIIY5N2VR	2023-11-07
https://access.redhat.com/security/cve/CVE-2020-5238	2021-05-18
https://bugzilla.redhat.com/show_bug.cgi?id=1854328	2021-05-18

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Github Flavored Markdown Project Search vendor "Github Flavored Markdown Project"		Github Flavored Markdown Search vendor "Github Flavored Markdown Project" for product "Github Flavored Markdown"				< 0.29.0.gfm.1 Search vendor "Github Flavored Markdown Project" for product "Github Flavored Markdown" and version " < 0.29.0.gfm.1"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				31 Search vendor "Fedoraproject" for product "Fedora" and version "31"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				32 Search vendor "Fedoraproject" for product "Fedora" and version "32"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				33 Search vendor "Fedoraproject" for product "Fedora" and version "33"		-		Affected