CVE-2026-79771Network attack vector

Service interruption via null-byte XSLT allocation leak

Published Aug 25, 2026 · Updated Aug 25, 2026

Memory leak in Nokogiri before 1.19.3 allows remote attackers to exhaust process memory via null-byte XSLT parameters. Nokogiri::XSLT::Stylesheet#transform fails to release an approximately 24–32-byte heap allocation when a Ruby string parameter contains a null byte and raises the expected string-handling exception. Sustained high-rate calls with raw attacker-controlled bytes are required to grow memory enough to interrupt a long-running process; transform results, data confidentiality, and memory integrity are unaffected.

CVSS severity6.9
Medium
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory leak in Nokogiri before 1.19.3 allows remote attackers to exhaust process memory via null-byte XSLT parameters. Nokogiri::XSLT::Stylesheet#transform fails to release an approximately 24–32-byte heap allocation when a Ruby string parameter contains a null byte and raises the expected string-handling exception. Sustained high-rate calls with raw attacker-controlled bytes are required to grow memory enough to interrupt a long-running process; transform results, data confidentiality, and memory integrity are unaffected.

The record

CVE
CVE-2026-79771
Published
Aug 25, 2026
Updated
Aug 25, 2026
Vendor
Sparkle Motion
Product
Nokogiri
Classifications
CWE-401, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <1.19.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Sparkle Motion · Nokogiriversion=0 <1.19.3

Published CVSS scores

5.3VulnCheck CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
6.9VulnCheck CNACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
T1499.003Application Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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