CVE-2026-86142 Memory corruption in libxml2
A heap-based buffer overflow in libxml2 allows attackers to execute arbitrary code or cause denial of service via crafted XPointer expressions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-86142?
CVE-2026-86142 is a medium-severity memory corruption vulnerability in Xmlsoft Libxml2, published on 5 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In libxml2 before 2.15.4, there is a heap-based buffer overflow in xmlXPtrEvalXPtrPart because of xmlXPtrEval xpointer length saturation.
Weakness: CWE-122
Which versions are affected by CVE-2026-86142?
It affects 1 product.
Linux distribution packages (13)
libxml2 AlmaLinux:8 | All versions | 2.9.7-21.el8_10.10 |
libxml2-devel AlmaLinux:8 | All versions | 2.9.7-21.el8_10.10 |
python3-libxml2 AlmaLinux:8 | All versions | 2.9.7-21.el8_10.10 |
libxml2-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 0:2.9.7-21.el8_10.10 |
libxml2-debugsource Red Hat:enterprise_linux:8::appstream | All versions | 0:2.9.7-21.el8_10.10 |
libxml2-devel Red Hat:enterprise_linux:8::appstream | All versions | 0:2.9.7-21.el8_10.10 |
python3-libxml2-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 0:2.9.7-21.el8_10.10 |
libxml2 Red Hat:enterprise_linux:8::baseos | All versions | 0:2.9.7-21.el8_10.10 |
libxml2-debuginfo Red Hat:enterprise_linux:8::baseos | All versions | 0:2.9.7-21.el8_10.10 |
libxml2-debugsource Red Hat:enterprise_linux:8::baseos | All versions | 0:2.9.7-21.el8_10.10 |
python3-libxml2 Red Hat:enterprise_linux:8::baseos | All versions | 0:2.9.7-21.el8_10.10 |
python3-libxml2-debuginfo Red Hat:enterprise_linux:8::baseos | All versions | 0:2.9.7-21.el8_10.10 |
libxml2 Rocky Linux:8 | All versions | 0:2.9.7-21.el8_10.10 |
Products include Xmlsoft Libxml2.
How do I fix CVE-2026-86142?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-86142 being exploited?
There is no known exploitation of CVE-2026-86142 in the wild and no public exploit code.
Other vulnerabilities in Xmlsoft Libxml2
Sources
Also known as ALSA-2026:80675, AZL-99720, BELL-CVE-2026-86142, CLSA-2026-1789381419, CLSA-2026-1789381872, CLSA-2026-1789382179 and 9 more.