LiveActive security incident?Get immediate response
CVE Record

CVE-2026-8177: XML::LibXML versions through 2.0210 for Perl read out-of-bounds heap memory when parsing XML node names containing truncated UTF-8 byte sequences

XML::LibXML versions through 2.0210 for Perl read out-of-bounds heap memory when parsing XML node names containing truncated UTF-8 byte sequences. A node name ending in the middle of a multi byte UTF-8 sequence causes the parser to read past the end of the input string into adjacent heap memory. Any Perl process that passes attacker controlled strings to XML::LibXML's DOM node-name methods can reach this path on the default API. The likely consequence is a crash, causing denial of service.

HighCVSS 7.5Not KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2026-8177 is a denial-of-service risk in Perl XML::LibXML. Malformed XML node names ending with incomplete UTF-8 can make a process read past allocated heap memory and likely crash. Systems parsing attacker-controlled XML or node names with affected XML::LibXML versions should be prioritized.

Executive priority

Treat this as a high-priority availability issue for internet-facing or externally fed Perl XML processing. It is less urgent than confirmed exploited code execution, but unauthenticated crashes can disrupt business services.

Technical view

XML::LibXML versions through 2.0210 can trigger CWE-125 out-of-bounds heap reads when DOM node-name parsing encounters truncated multibyte UTF-8. The CVSS 3.1 vector is AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H, indicating unauthenticated remote availability impact, with no cited confidentiality or integrity impact.

Likely exposure

Exposure is most likely in Perl services, batch jobs, or web applications that pass attacker-controlled strings to XML::LibXML DOM node-name methods. The source bundle has inconsistent affected metadata, so validate installed XML-LibXML package versions against upstream and distribution advisories.

Exploitation context

The bundle does not cite KEV listing or active exploitation. The described attack condition is low complexity and does not require authentication or user interaction, but the supported consequence is process crash and denial of service, not code execution.

Researcher notes

Primary evidence points to an out-of-bounds heap read in default API node-name handling. The affected-version metadata appears incomplete or contradictory versus the description, so researchers should reconcile upstream issue, pull request, patch, and vendor advisories before scoping.

Mitigation direction

  • Apply the upstream XML-LibXML patch or vendor package updates.
  • Review Red Hat errata if using Red Hat packaged XML::LibXML.
  • Upgrade XML::LibXML when your distribution or CPAN provides a fixed release.
  • Reduce attacker control over XML node names where feasible.
  • Add input validation or rejection for malformed UTF-8 XML names.

Validation and detection

  • Inventory Perl applications importing XML::LibXML or XML-LibXML packages.
  • Check installed XML::LibXML versions against versions through 2.0210.
  • Identify paths accepting untrusted XML or node-name strings.
  • Confirm vendor advisories apply to your operating system packages.
  • Run regression tests covering malformed UTF-8 rejection and parser error handling.
Prepared
Confidence
medium
Sources
11

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-125: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2026-8177 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
High
CVSS
7.5 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

2CVSS vectors
6Timeline events
3ADP providers
10Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: yesTechnical Impact: partial

CVSS vector scores

2 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6CISA-ADP
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6redhat-SADP

Vulnerability scoring details

Base CVSS 3.1 score

7.5High
CVSS 3.1 vector shape for CVE-2026-8177Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. Source timelineCPANSec

    Patch submitted in upstream PR.

  2. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  3. ADP timelineredhat-SADP

    Made public.

  4. CVE publishedCVE Program

    The CVE record was published.

  5. ADP timelineredhat-SADP

    Reported to Red Hat.

  6. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CVECVE Program Container
CISA-ADPCISA ADP Vulnrichment
cvssV3_1other:ssvc
redhat-SADPperl-XML-LibXML: XML::LibXML: Denial of Service via truncated UTF-8 in XML node names
other:Red Hat severity ratingcvssV3_1
  • 2026-05-10T22:00:53.601Z: Reported to Red Hat.
  • 2026-05-10T20:48:51.816Z: Made public.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
SHLOMIFXML::LibXMLXML-LibXML, 0unaffected
Weakness

CWE details

CWE-125

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-125 · source CWE mapping

Out-of-bounds Read

Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs