CVE-2026-86143
Fixed in a distro release EPSS <1%CVSS 6.9
In xmlIO in libxml2 before 2.15.4, an inconsistency in xmlOutputWriteCallback and xmlBufUse causes negative lengths to reach write callbacks, aka a lack of a check for integer overflow before calling writecallback. This has security relevance for many types of uses of that length value within a callback.
Products: xmlsoft libxml2
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| AlmaLinux 10 | libxml2 | 2.12.5-10.el10_2.4 |
| AlmaLinux 10 | libxml2-devel | 2.12.5-10.el10_2.4 |
| AlmaLinux 10 | libxml2-static | 2.12.5-10.el10_2.4 |
| AlmaLinux 10 | python3-libxml2 | 2.12.5-10.el10_2.4 |
| AlmaLinux 8 | libxml2 | 2.9.7-21.el8_10.9 |
| AlmaLinux 8 | libxml2-devel | 2.9.7-21.el8_10.9 |
| AlmaLinux 8 | python3-libxml2 | 2.9.7-21.el8_10.9 |
| AlmaLinux 9 | libxml2 | 2.9.13-14.el9_8.5 |
| AlmaLinux 9 | libxml2-devel | 2.9.13-14.el9_8.5 |
| AlmaLinux 9 | python3-libxml2 | 2.9.13-14.el9_8.5 |
| Amazon Linux 2 | libxml2 | 2.9.1-6.amzn2.5.27 |
| Amazon Linux 2 | libxml2-devel | 2.9.1-6.amzn2.5.27 |
| Amazon Linux 2 | libxml2-python | 2.9.1-6.amzn2.5.27 |
| Amazon Linux 2 | libxml2-static | 2.9.1-6.amzn2.5.27 |
| Amazon Linux 2023 | libxml2 | 2.10.4-1.amzn2023.0.21 |
| Amazon Linux 2023 | libxml2-devel | 2.10.4-1.amzn2023.0.21 |
| Amazon Linux 2023 | libxml2-static | 2.10.4-1.amzn2023.0.21 |
| Amazon Linux 2023 | python3-libxml2 | 2.10.4-1.amzn2023.0.21 |
| Debian 12 | libxml2 | no fix |
| Debian 13 | libxml2 | no fix |
| Debian 14 | libxml2 | 2.15.4+dfsg-1 |
| Red Hat Enterprise Linux 10.2 | libxml2 | 0:2.12.5-10.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | libxml2-debuginfo | 0:2.12.5-10.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | libxml2-debugsource | 0:2.12.5-10.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | libxml2-devel | 0:2.12.5-10.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | libxml2-static | 0:2.12.5-10.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | python3-libxml2 | 0:2.12.5-10.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | python3-libxml2-debuginfo | 0:2.12.5-10.el10_2.4 |
| Red Hat Enterprise Linux 8 | libxml2 | 0:2.9.7-21.el8_10.9 |
| Red Hat Enterprise Linux 8 | libxml2-debuginfo | 0:2.9.7-21.el8_10.9 |
| Red Hat Enterprise Linux 8 | libxml2-debugsource | 0:2.9.7-21.el8_10.9 |
| Red Hat Enterprise Linux 8 | libxml2-devel | 0:2.9.7-21.el8_10.9 |
| Red Hat Enterprise Linux 8 | python3-libxml2 | 0:2.9.7-21.el8_10.9 |
| Red Hat Enterprise Linux 8 | python3-libxml2-debuginfo | 0:2.9.7-21.el8_10.9 |
| Red Hat Enterprise Linux 9 | libxml2 | 0:2.9.13-14.el9_8.5 |
| Red Hat Enterprise Linux 9 | libxml2-debuginfo | 0:2.9.13-14.el9_8.5 |
| Red Hat Enterprise Linux 9 | libxml2-debugsource | 0:2.9.13-14.el9_8.5 |
| Red Hat Enterprise Linux 9 | libxml2-devel | 0:2.9.13-14.el9_8.5 |
| Red Hat Enterprise Linux 9 | python3-libxml2 | 0:2.9.13-14.el9_8.5 |
| Red Hat Enterprise Linux 9 | python3-libxml2-debuginfo | 0:2.9.13-14.el9_8.5 |
| Red Hat hummingbird 1 | libxml2 | 0:2.15.4-0.1.hum1 |
| Red Hat hummingbird 1 | libxml2-16 | 0:2.15.4-0.1.hum1 |
| Red Hat hummingbird 1 | libxml2-devel | 0:2.15.4-0.1.hum1 |
| Red Hat hummingbird 1 | libxml2-static | 0:2.15.4-0.1.hum1 |
| Red Hat hummingbird 1 | python3-libxml2 | 0:2.15.4-0.1.hum1 |
| Rocky Linux 10 | libxml2 | 0:2.12.5-10.el10_2.4 |
| Rocky Linux 8 | libxml2 | 0:2.9.7-21.el8_10.9 |
| Rocky Linux 9 | libxml2 | 0:2.9.13-14.el9_8.5 |
| Ubuntu 22.04 LTS | libxml2 | 2.9.13+dfsg-1ubuntu0.14 |
| Ubuntu 24.04 LTS | libxml2 | 2.9.14+dfsg-1.3ubuntu3.10 |
| Ubuntu 26.04 LTS | libxml2 | 2.15.2+dfsg-0.1ubuntu0.3 |
| Ubuntu Pro 14.04 LTS | libxml2 | 2.9.1+dfsg1-3ubuntu4.13+esm13 |
| Ubuntu Pro 16.04 LTS | libxml2 | 2.9.3+dfsg1-1ubuntu0.7+esm14 |
| Ubuntu Pro 18.04 LTS | libxml2 | 2.9.4+dfsg1-6.1ubuntu1.9+esm9 |
| Ubuntu Pro 20.04 LTS | libxml2 | 2.9.10+dfsg-5ubuntu0.20.04.10+esm6 |