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TI-2026-55247 Aliases CVE-2026-79770GHSA-c4rq-3m3g-8wgx

Nokogiri before 1.19.3 ReDoS via CSS selector tokenizer

Priority MEDIUM 44CWE-1333Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-1333.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00493 42nd percentileScored 2026-11-07
Fix Fixed nokogiri (sparklemotion): 1.19.3nokogiri (RubyGems): 1.19.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
sparklemotionnokogiribefore 1.19.31.19.3Patch availableCNA
—nokogiri (RubyGems)before 1.19.31.19.3Patch availableGHSA-c4rq-3m3g-8wgx
  • nokogiri Vendorsparklemotion Affected before 1.19.3 Fixed in 1.19.3 Patch available CNA
  • nokogiri (RubyGems) Vendor— Affected before 1.19.3 Fixed in 1.19.3 Patch available GHSA-c4rq-3m3g-8wgx

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nokogiri:nokogiri:*:*:*:*:*:ruby:*:*before 1.19.3Vulnerablesparklemotion
  • cpe:2.3:a:nokogiri:nokogiri:*:*:*:*:*:ruby:*:* Versions before 1.19.3 Vulnerable ·sparklemotion

Remediation

  • Fix · CNA nokogiri (sparklemotion) Fixed in 1.19.3
  • Fix · GHSA-c4rq-3m3g-8wgx nokogiri (RubyGems) Fixed in 1.19.3 Advisory →

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    sparklemotion nokogiri 1.19.3

    2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-55248 Nokogiri before 1.19.3 Memory Leak via XSLT TransformPriority LOW 37
    Show all 2 records →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

Not affected: 2 products
  • Red Hat 3scale API Management Platform 2
  • Red Hat Satellite 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-79770
  2. 2026-10-03 Alias added: GHSA-c4rq-3m3g-8wgx

References

Advisory 2

Other 1

  • TI-2022-11724 Improper Handling of Unexpected Data Type in Nokogiri CVSS 3.1HIGH 8.2
  • TI-2018-15259 zlib before 1.2.12 allows memory corruption when deflating (i.e., when compressing) if… CVSS 3.1HIGH 7.5
  • TI-2019-03885 OS command injection in Nokogiri CVSS 3.1CRITICAL 9.8
  • TI-2022-07536 Unchecked return value from xmlTextReaderExpand in Nokogiri CVSS 3.1HIGH 7.5
  • TI-2022-08648 Inefficient Regular Expression Complexity in Nokogiri CVSS 3.1HIGH 7.5
  • TI-2026-55248 Nokogiri before 1.19.3 Memory Leak via XSLT Transform CVSS 4.0MEDIUM 6.9
See all 20 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences