CVE-2026-79770

Nokogiri versions before 1.19.3 contain regular expression denial of service vulnerabilities in the CSS selector tokenizer affecting string-literal and identifier tokenization. Attackers can inject adversarial CSS selectors into methods like Node#css, Node#at_css, and Searchable#search to cause exponential regex backtracking and denial of service.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-c4rq-3m3g-8wgx	Mitigation Vendor Advisory
https://www.vulncheck.com/advisories/nokogiri-before-redos-via-css-selector-tokenizer	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nokogiri:nokogiri:*:*:*:*:*:ruby:*:*

History

No history.

Information

Published : 2026-08-25 16:17

Updated : 2026-09-01 14:56

NVD link : CVE-2026-79770

Mitre link : CVE-2026-79770

CVE.ORG link : CVE-2026-79770

JSON object : View

Products Affected

nokogiri

nokogiri

CWE

CWE-1333

Inefficient Regular Expression Complexity

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