CVE-2026-86138
published 2026-09-05CVE-2026-86138: In libxml2 before 2.15.4, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
PriorityP345high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.13%
2.5th percentile
In libxml2 before 2.15.4, xmlDictAddQString in dict.c has an integer overflow and resultant heap-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_redhat6.9MEDIUM
vendor_ubuntu5.5MEDIUM
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Ubuntu
libxml2 vulnerabilities
vendor_ubuntu·2026-10-08·CVSS 5.5
CVE-2026-86144 [MEDIUM] libxml2 vulnerabilities
Title: libxml2 vulnerabilities
Summary: Several security issues were fixed in libxml2.
Yirou Yang discovered that libxml2 incorrectly handled certain XML
catalogs. If a user or automated system was tricked into processing a
specially crafted XML catalog, an attacker could possibly use this issue to
cause libxml2 to crash, resulting in a denial of service. (CVE-2026-76781)
It was discovered that libxml2 incorrectly handled certain large qualified
names, leading to a heap-based buffer overflow. An attacker could possibly
use this issue to cause libxml2 to crash, resulting in a denial of service,
or possibly execute arbitrary code. (CVE-2026-86138)
It was discovered that libxml2 incorrectly handled escaping certain large
URI strings. An attacker could possibly use this issue to cause libx
Red Hat
libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow
vendor_redhat·2026-09-05·CVSS 6.9
CVE-2026-86138 [MEDIUM] CWE-787 libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow
libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow
A flaw was found in libxml2. The `xmlDictAddQString` function in `dict.c` is vulnerable to an integer overflow, which can lead to a heap-based buffer overflow. This vulnerability could allow a local attacker to achieve arbitrary code execution.
Package: libxml2 (Red Hat Hardened Images) - Affected
Package: swift-lang (Red Hat Hardened Images) - Affected
GHSA
In libxml2 before 2.15.4, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
ghsa_unreviewed·2026-09-05
CVE-2026-86138 [MEDIUM] CWE-190 In libxml2 before 2.15.4, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
In libxml2 before 2.15.4, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-86138 pcem: libxml2: Arbitrary code execution via heap-based buffer overflow [fedora-all]
bugzilla·2026-09-09·CVSS 6.9
CVE-2026-86138 [MEDIUM] CVE-2026-86138 pcem: libxml2: Arbitrary code execution via heap-based buffer overflow [fedora-all]
CVE-2026-86138 pcem: libxml2: Arbitrary code execution via heap-based buffer overflow [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, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
Bugzilla
CVE-2026-86138 qt6-qtwebengine: libxml2: Arbitrary code execution via heap-based buffer overflow [epel-all]
bugzilla·2026-09-09·CVSS 6.9
CVE-2026-86138 [MEDIUM] CVE-2026-86138 qt6-qtwebengine: libxml2: Arbitrary code execution via heap-based buffer overflow [epel-all]
CVE-2026-86138 qt6-qtwebengine: libxml2: Arbitrary code execution via heap-based buffer overflow [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, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
Bugzilla
CVE-2026-86138 mingw-libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow [fedora-all]
bugzilla·2026-09-09·CVSS 6.9
CVE-2026-86138 [MEDIUM] CVE-2026-86138 mingw-libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow [fedora-all]
CVE-2026-86138 mingw-libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow [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, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
Bugzilla
CVE-2026-86138 libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow [fedora-all]
bugzilla·2026-09-09·CVSS 6.9
CVE-2026-86138 [MEDIUM] CVE-2026-86138 libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow [fedora-all]
CVE-2026-86138 libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow [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, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
Bugzilla
CVE-2026-86138 qt5-qtwebengine: libxml2: Arbitrary code execution via heap-based buffer overflow [fedora-all]
bugzilla·2026-09-09·CVSS 6.9
CVE-2026-86138 [MEDIUM] CVE-2026-86138 qt5-qtwebengine: libxml2: Arbitrary code execution via heap-based buffer overflow [fedora-all]
CVE-2026-86138 qt5-qtwebengine: libxml2: Arbitrary code execution via heap-based buffer overflow [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, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
Bugzilla
CVE-2026-86138 mingw-libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow [epel-all]
bugzilla·2026-09-09·CVSS 6.9
CVE-2026-86138 [MEDIUM] CVE-2026-86138 mingw-libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow [epel-all]
CVE-2026-86138 mingw-libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow [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, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
Bugzilla
CVE-2026-86138 qt5-qtwebengine: libxml2: Arbitrary code execution via heap-based buffer overflow [epel-all]
bugzilla·2026-09-09·CVSS 6.9
CVE-2026-86138 [MEDIUM] CVE-2026-86138 qt5-qtwebengine: libxml2: Arbitrary code execution via heap-based buffer overflow [epel-all]
CVE-2026-86138 qt5-qtwebengine: libxml2: Arbitrary code execution via heap-based buffer overflow [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, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
Bugzilla
CVE-2026-86138 libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow
bugzilla·2026-09-05·CVSS 6.9
CVE-2026-86138 [MEDIUM] CVE-2026-86138 libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow
CVE-2026-86138 libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow
In libxml2 before 2.15.4, xmlDictAddQString in dict.c has an integer overflow and resultant heap-based buffer overflow.
2026-09-05
Published