Medium severity · published Aug 25, 2026
CVE-2026-79771
Nokogiri before 1.19.3 Memory Leak via XSLT Transform
5.3
CVSS
0.4%
EPSS
No
On KEV
Description
Nokogiri versions before 1.19.3 contain a memory leak in the XSLT Stylesheet transform method when processing Ruby strings containing null bytes. Attackers can exploit this by passing attacker-controlled input with null bytes to transform parameters, causing heap allocations to leak and enabling denial of service against long-running processes.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 36% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NO
nokogiri · sparklemotion
before 1.19.3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-79771
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-79771
Vendor Advisory
https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-v2fc-qm4h-8hqv
Third Party Advisory
https://www.vulncheck.com/advisories/nokogiri-before-memory-leak-via-xslt-transform
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