What is the CVSS score of CVE-2021-27291?

CVE-2021-27291 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 3.8%.

Is there a public PoC exploit available for CVE-2021-27291?

Yes, a public proof-of-concept exploit is available for CVE-2021-27291. Prioritise patching immediately. EPSS: 3.8%.

Is there a patch available for CVE-2021-27291?

Yes, a patch is available for CVE-2021-27291. Update the affected software to the latest version immediately.

Pygments CVE-2021-27291

HIGH

Inefficient Regular Expression Complexity (ReDoS) (CWE-1333)

2021-03-17 cve@mitre.org

Denial Of Service Pygments Debian Linux Fedora

7.5

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

7.5 HIGH

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

CVE Published

Mar 17, 2021 - 13:15 nvd

HIGH 7.5

DescriptionNVD

In pygments 1.1+, fixed in 2.7.4, the lexers used to parse programming languages rely heavily on regular expressions. Some of the regular expressions have exponential or cubic worst-case complexity and are vulnerable to ReDoS. By crafting malicious input, an attacker can cause a denial of service.

AnalysisAI

In pygments 1.1+, fixed in 2.7.4, the lexers used to parse programming languages rely heavily on regular expressions. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.

Technical ContextAI

This vulnerability is classified under CWE-1333. In pygments 1.1+, fixed in 2.7.4, the lexers used to parse programming languages rely heavily on regular expressions. Some of the regular expressions have exponential or cubic worst-case complexity and are vulnerable to ReDoS. By crafting malicious input, an attacker can cause a denial of service. Affected products include: Pygments, Debian Debian Linux, Fedoraproject Fedora.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.