PatchSiren cyber security CVE debrief
CVE-2026-8177 SHLOMIF CVE debrief
CVE-2026-8177 is a high-severity vulnerability in XML::LibXML for Perl, affecting versions up to 2.0210. The issue arises when parsing XML node names with truncated UTF-8 byte sequences, causing an out-of-bounds heap read. This can lead to a denial-of-service (DoS) attack, likely resulting in a crash. Any Perl process passing attacker-controlled strings to XML::LibXML's DOM node-name methods can be exploited. The vulnerability has a CVSS score of 7.5 and is classified as HIGH. The CVE was published on May 10, 2026, and last modified on June 30, 2026.
- Vendor
- SHLOMIF
- Product
- XML::LibXML
- CVSS
- HIGH 7.5
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-05-10
- Original CVE updated
- 2026-09-18
- Advisory published
- 2026-05-10
- Advisory updated
- 2026-09-18
Who should care
Organizations using Perl processes that parse XML node names, especially those passing attacker-controlled strings to XML::LibXML's DOM node-name methods, should prioritize patching. This includes developers and administrators of systems using XML::LibXML for XML processing. Red Hat and other Linux distributions may also be affected, as indicated by Red Hat's security advisories.
Technical summary
The vulnerability occurs when an XML node name ends in the middle of a multi-byte UTF-8 sequence, causing the parser to read past the end of the input string into adjacent heap memory. This out-of-bounds read can lead to a crash, resulting in a denial-of-service (DoS) attack. The issue is triggered by passing attacker-controlled strings to XML::LibXML's DOM node-name methods. The CVSS vector is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H, indicating a high severity. CWE-125 is associated with this vulnerability.
Defensive priority
High priority should be given to patching XML::LibXML to version 2.0211 or later. In the meantime, validate and sanitize all input strings to prevent truncated UTF-8 sequences from being passed to XML::LibXML's DOM node-name methods.
Recommended defensive actions
- Patch XML::LibXML to version 2.0211 or later
- Validate and sanitize all input strings to prevent truncated UTF-8 sequences
- Monitor for suspicious XML parsing activity
- Implement additional security measures to prevent DoS attacks
- Review and update XML processing workflows to ensure secure practices
Evidence notes
The CVE record and NVD detail provide official information on the vulnerability. Red Hat has also published advisories and a bug report related to this issue. The XML::LibXML project has released patches and updates to address the vulnerability.
Sources and references
Verified primary and authoritative sources
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CVE-2026-8177 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2026-8177
CVE Program - Official CVE Program record with source-provided CVE metadata.
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CVE-2026-8177 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2026-8177
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
Supplemental references
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Source reference
Unverified legacy reference
URL: https://github.com/cpan-authors/XML-LibXML/commit/15652bd905a6c9dda59a81b14d4766adbbae2ea8.patch
9b29abf9-4ab0-4765-b253-1875cd9b441e
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Source reference
Unverified legacy reference
URL: https://github.com/cpan-authors/XML-LibXML/issues/146
9b29abf9-4ab0-4765-b253-1875cd9b441e
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Source reference
Unverified legacy reference
URL: https://github.com/cpan-authors/XML-LibXML/pull/149
9b29abf9-4ab0-4765-b253-1875cd9b441e
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Source reference
Unverified legacy reference
URL: https://access.redhat.com/security/cve/CVE-2026-8177
0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.