mediumCVSS 5.3Vulnerability

GHSA-v2fc-qm4h-8hqv

## Summary Nokogiri's `Nokogiri::XSLT::Stylesheet#transform` leaks a small heap allocation when passed a Ruby string parameter containing a null byte. For applications that pass attacker-controlled input through `XSLT.transform` parameters, this may be a vector for a denial of service attack against long-running processes. ## Mitigation Upgrade to Nokogiri `>= 1.19.3`. Users may also be able to mitigate this issue without upgrading by validating untrusted transform parameters before passing them to `Nokogiri::XSLT::Stylesheet#transform`. ## Severity The Nokogiri maintainers have evaluated this as **Moderate Severity**, CVSS 5.3. Each leaked allocation is approximately 24–32 bytes, so meaningful memory growth requires sustained attacker-controlled traffic at high call rates. The bug does not cause memory corruption, information disclosure, or any change in the behavior of the transform itself, and the string-handling exception is raised as expected. Applications that do not pass raw attacker-controlled bytes to XSLT parameters are unlikely to be affected in practice. ## Resources - [CWE-401: Missing Release of Memory after Effective Lifetime](https://cwe.mitre.org/data/definitions/401.html) ## Credit This vulnerability was responsibly reported by @Captainjack-kor.

Properties

ghsa_id
GHSA-v2fc-qm4h-8hqv
severity
medium
summary
Nokogiri XSLT transform has a memory leak
cvss_score
5.3
cve_id
GHSA-v2fc-qm4h-8hqv
cvss_vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
is_ghsa_only
true
ghsa_published
2026-05-06T18:27:38Z
source_url
https://github.com/advisories/GHSA-v2fc-qm4h-8hqv
ghsa_updated
2026-05-06T18:27:39Z

Related Entities (4)

HAS_WEAKNESS (1)

[Weakness]Missing Release of Memory after Effective Lifetime

REPORTED_BY (1)

[Source]GitHub Advisory Database

VULNERABLE_TO (1)

[Software]rubygems/nokogiri

AFFECTS (1)

[Software]rubygems/nokogiri

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GHSA-v2fc-qm4h-8hqv (CVSS 5.3) — Ninja Signal Threat Intelligence | Ninja Signal