xmlsoft libxml2 up to 2.15.3 valid.c xmlSnprintfElements stack-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.5$0-$5k0.81+

Summaryinfo

A vulnerability has been found in xmlsoft libxml2 up to 2.15.3 and classified as problematic. Affected by this issue is the function xmlSnprintfElements of the file valid.c. Performing a manipulation results in stack-based overflow. This vulnerability was named CVE-2026-86140. The attack needs to be approached locally. There is no available exploit.

Detailsinfo

A vulnerability classified as problematic has been found in xmlsoft libxml2 up to 2.15.3. This affects the function xmlSnprintfElements of the file valid.c. The manipulation with an unknown input leads to a stack-based overflow vulnerability. CWE is classifying the issue as CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-86140 since 09/05/2026. The exploitability is told to be easy. An attack has to be approached locally. Technical details are known, but no exploit is available.

Upgrading to version 2.15.4 eliminates this vulnerability.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.6
VulDB Meta Temp Score: 6.5

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.0
CNA Vector (MITRE): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Stack-based overflow
CWE: CWE-121 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libxml2 2.15.4

Timelineinfo

09/05/2026 Advisory disclosed
09/05/2026 +0 days CVE reserved
09/05/2026 +0 days VulDB entry created
09/05/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-86140 (🔒)
GCVE (CVE): GCVE-0-2026-86140
GCVE (VulDB): GCVE-100-399213

Entryinfo

Created: 09/05/2026 06:52
Changes: 09/05/2026 06:52 (66)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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