CVE-2026-79770 json
Nokogiri before 1.19.3 ReDoS via CSS selector tokenizer
published 2026-05-06 6 mo ago modified 2026-09-16 53 d ago also GHSA-c4rq-3m3g-8wgx , EUVD-2026-65528
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 42%
- public exploits
- 0
- none known
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.
Patch / fix
- rubygems nokogiri 1.19.3
- sparklemotion nokogiri 1.19.3
- ruby-nokogiri Debian 14 1.19.3+dfsg-1
debian advisories DEBIAN-CVE-2026-79770
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-79770 updated cvss 7.5
nokogiri: Nokogiri: Denial of Service via crafted CSS selectors
-
Red Hat 3scale API Management Platform 2 3scale-amp2/zync-rhel9, 3scale-amp2/system-rhel8, 3scale-amp2/system-rhel9, 3scale-amp2/backend-rhel8, 3scale-amp2/toolbox-rhel9not affected: vulnerable code not in execute path
-
Red Hat Satellite 6 tfm-rubygem-graphql, tfm-rubygem-amazing_printnot affected: component not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| rubygems | nokogiri | <1.19.3 |
1.19.3 |
Affected products
- sparklemotion nokogiri
Classification
- Weakness
-
- CWE-1333 Inefficient Regular Expression Complexity
References
-
github.com
/sparklemotion/nokogiri/security/advisories/GHSA-c4rq-3m3g-8wgx
vendor-advisory, web, mitigation
-
vulncheck.com
/advisories/nokogiri-before-redos-via-css-selector-tokenizer
third-party-advisory, web
-
nvd.nist.gov
/vuln/detail/CVE-2026-79770
advisory
-
github.com
/sparklemotion/nokogiri
package
Sources
- CVE List CVE-2026-79770
- GitHub Advisory GHSA-c4rq-3m3g-8wgx
- NVD CVE-2026-79770
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.