CVE-2026-86140
published 2026-09-05CVE-2026-86140: In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
PriorityP347high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.16%
4.5th percentile
In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| ubuntu | libxml2 | — | — |
| xmlsoft | libxml2 | < 2.15.4 | 2.15.4 |
| xmlsoft | libxml2 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
vendor_ubuntu8.5HIGH
vendor_redhat8.0HIGH
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Ubuntu
libxml2 vulnerabilities
vendor_ubuntu·2026-09-21·CVSS 8.5
CVE-2026-86140 [HIGH] libxml2 vulnerabilities
Title: libxml2 vulnerabilities
Summary: Several security issues were fixed in libxml2.
It was discovered that libxml2 incorrectly handled certain XML elements
under certain circumstances. An attacker could possibly use this issue to
cause libxml2 to crash or execute arbitrary code. (CVE-2026-86140)
It was discovered that libxml2 incorrectly handled certain XML documents
when used with Python bindings. A remote attacker could possibly use this
issue to cause applications using libxml2 to crash, resulting in a denial
of service. (CVE-2026-74860)
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements
vendor_redhat·2026-09-05·CVSS 8.0
CVE-2026-86140 [HIGH] CWE-120 libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements
libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements
A flaw was found in libxml2, a software library for parsing XML (Extensible Markup Language) documents. The `xmlSnprintfElements` function within this library is vulnerable to a stack-based buffer overflow, a type of memory corruption. A local attacker could exploit this flaw without requiring privileges or user interaction, potentially leading to arbitrary code execution or a denial of service.
Package: libxml2 (Red Hat Hardened Images) - Affected
Package: swift-lang (Red Hat Hardened Images) - Affected
GHSA
In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
ghsa_unreviewed·2026-09-05
CVE-2026-86140 [HIGH] CWE-121 In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
VulDB
xmlsoft libxml2 up to 2.15.3 valid.c xmlSnprintfElements stack-based overflow (Nessus ID 343107)
vuldb·2026-09-05·CVSS 8.0
CVE-2026-86140 [HIGH] xmlsoft libxml2 up to 2.15.3 valid.c xmlSnprintfElements stack-based overflow (Nessus ID 343107)
A vulnerability, which was classified as problematic, was found in xmlsoft libxml2 up to 2.15.3. Affected by this vulnerability is the function xmlSnprintfElements of the file valid.c. Such manipulation leads to stack-based buffer overflow.
This vulnerability is uniquely identified as CVE-2026-86140. Local access is required to approach this attack. No exploit exists.
You should upgrade the affected component.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-86140 libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [fedora-all]
bugzilla·2026-09-08·CVSS 8.0
CVE-2026-86140 [HIGH] CVE-2026-86140 libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [fedora-all]
CVE-2026-86140 libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
Bugzilla
CVE-2026-86140 mingw-libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [fedora-all]
bugzilla·2026-09-08·CVSS 8.0
CVE-2026-86140 [HIGH] CVE-2026-86140 mingw-libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [fedora-all]
CVE-2026-86140 mingw-libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
Bugzilla
CVE-2026-86140 mingw-libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [epel-all]
bugzilla·2026-09-08·CVSS 8.0
CVE-2026-86140 [HIGH] CVE-2026-86140 mingw-libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [epel-all]
CVE-2026-86140 mingw-libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [epel-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
Bugzilla
CVE-2026-86140 pcem: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [fedora-all]
bugzilla·2026-09-08·CVSS 8.0
CVE-2026-86140 [HIGH] CVE-2026-86140 pcem: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [fedora-all]
CVE-2026-86140 pcem: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
Bugzilla
CVE-2026-86140 libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements
bugzilla·2026-09-05·CVSS 8.0
CVE-2026-86140 [HIGH] CVE-2026-86140 libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements
CVE-2026-86140 libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements
In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.
2026-09-05
Published