libxslt Type Confusion vulnerability that affects Nokogiri

Description

In numbers.c in libxslt 1.1.33, a type holding grouping characters of an xsl:number instruction was too narrow and an invalid character/length combination could be passed to xsltNumberFormatDecimal, leading to a read of uninitialized stack data.

Nokogiri prior to version 1.10.5 used a vulnerable version of libxslt. Nokogiri 1.10.5 updated libxslt to version 1.1.34 to address this and other vulnerabilities in libxslt.

Basic information

Type
reviewed
Severity
high
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Not specified
Published (advisory)
2022-05-24 16:49:07 UTC
Updated
2026-06-09 10:21:53 UTC
GitHub reviewed
2023-03-08 19:57:56 UTC
NVD published
2019-06-30

EPSS Score

Score Percentile
1.01% 77.10%

CVSS Scores

Base score Version Severity Vector
7.5 3.0
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.

Identifiers

CWEs

CWE id Name
CWE-843 Access of Resource Using Incompatible Type ('Type Confusion')

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
rubygems nokogiri < 1.10.5 1.10.5

References

cvelogic Threat Intelligence