Ubuntu libxmltok Updates Fix Two Vulnerabilities
Tech GuruQuick Answer
Ubuntu published USN-8872-1 for libxmltok on Ubuntu 24.04 (noble) LTS, Ubuntu 22.04 (jammy) LTS, Ubuntu 20.04 (focal) ESM, Ubuntu 18.04 (bionic) ESM, Ubuntu 16.04 (xenial) ESM. Ubuntu does not state a CVSS base score in the notice. Install the fixed source-package version for the exact supported or ESM release and validate dependent XML-processing workloads.
Match USN-8872-1 To Ubuntu Releases And Update
What to do now: Inventory affected Ubuntu releases, compare installed libxmltok source-package versions with USN-8872-1, install the supported updates, validate dependent workloads, and retain evidence.
Last verified: 2026-10-06 UTC. Recheck the authoritative advisory and supported distribution channel before changing production.
Scope And Authority
| Product scope | libxmltok on Ubuntu 24.04 (noble) LTS, Ubuntu 22.04 (jammy) LTS, Ubuntu 20.04 (focal) ESM, Ubuntu 18.04 (bionic) ESM, Ubuntu 16.04 (xenial) ESM |
|---|---|
| Advisory | USN-8872-1 |
| CVEs | CVE-2026-56404, CVE-2026-56405 |
| Authoritative release date | 2026-10-05 23:54:25.261094 UTC |
| Authority revision date | 2026-10-05 23:54:25.261094 UTC |
| Affected versions | The Ubuntu releases and libxmltok source packages enumerated in USN-8872-1: Ubuntu 24.04 (noble) LTS, Ubuntu 22.04 (jammy) LTS, Ubuntu 20.04 (focal) ESM, Ubuntu 18.04 (bionic) ESM, Ubuntu 16.04 (xenial) ESM. |
| Fixed version | bionic: libxmltok 1.2-4ubuntu0.18.04.1~esm7 / focal: libxmltok 1.2-4ubuntu0.20.04.1~esm7 / jammy: libxmltok 1.2-4ubuntu0.22.04.1~esm7 / noble: libxmltok 1.2-4.1ubuntu2.24.0.4.1+esm5 / xenial: libxmltok 1.2-3ubuntu0.1~esm1 |
| CVSS base score | Not provided by the authority |
| CVSS severity | Not provided by the authority |
| Exploitation status | Not stated by the authority; no exploitation claim is inferred. |
What Changed
libxmltok could be made to crash if it opened a specially crafted file. In general, a standard system update will make all the necessary changes.
What To Validate Now
- Inventory. Locate systems on Ubuntu 24.04 (noble) LTS, Ubuntu 22.04 (jammy) LTS, Ubuntu 20.04 (focal) ESM, Ubuntu 18.04 (bionic) ESM, Ubuntu 16.04 (xenial) ESM; record the installed libxmltok source package, repository pocket, Ubuntu Pro or ESM entitlement where applicable, owner, exposure, and dependencies.
- Establish applicability. Match the Ubuntu codename and source-package version to USN-8872-1. Do not infer applicability from a binary package name or CVE count alone.
- Remediate. Install the fixed libxmltok source-package version listed in USN-8872-1 through the supported security or ESM Apps channel for the exact Ubuntu release.
- Validate. Confirm the installed source-package version, exercise representative XML parsing and dependent application paths, monitor for crashes or regressions, and document any exception.
- Retain evidence. Preserve asset and owner identifiers, the applicability decision, before-and-after versions, change approval, installation output, validation results, and any exception or rollback record.
Operational Cautions
Some affected releases require Ubuntu Pro or ESM Apps entitlement. Coordinate application or service restart requirements and preserve package-manager output, before-and-after versions, validation results, and rollback evidence.
Evidence To Retain
- Exact product, release stream, package or application version, enabled feature, environment, and accountable owner.
- UTC timestamps, authority revision, approved change record, installer or package-manager output, and resulting version.
- Relevant logs and monitoring evidence, test results, exceptions, compensating controls, and rollback decisions.
Related TechGeeks Resources
Authoritative References
Correction policy: If the authority changes affected versions, fixed versions, severity, exploitation information, mitigations, or required action, TechGeeks will update this notice and its verification date.
