CVE-2026-93990

Severity: Important

Published: 2026-09-19

Expat through 2.8.4 fails to validate low surrogates following high surrogates in UTF-16 input, allowing malformed UTF-16 sequences to be accepted.

Exploit evidence

No public exploit evidence reported by NVD

Last checked: 2026-09-28 17:53 UTC

No exploitation evidence · CISA Coordinator (Assessed 2026-09-21 15:10 UTC)

NVD evidence for CVE-2026-93990 is reported, not independently verified by Package Alert. It does not establish exploit reliability or applicability to a particular package or environment.

References

Fix Status by Distribution

Fix evidence last checked: 2026-10-24 08:47 UTC

Fixed in:

AlmaLinux 10
- ALSA-2026:74001 · Published 2026-10-01
AlmaLinux 8
- ALSA-2026:72448 · Published 2026-09-28
AlmaLinux 9
- ALSA-2026:72663 · Published 2026-10-01
Debian 12 (Bookworm)
- DLA-4807-1 · Published 2026-10-01
Debian 13 (Trixie)
- DSA-6566-1 · Published 2026-10-16
Oracle Linux 10
- ELSA-2026-88248 · Published 2026-10-22
- ELSA-2026-74001 · Published 2026-10-01
Oracle Linux 8
- ELSA-2026-72448 · Published 2026-09-29
Oracle Linux 9
- ELSA-2026-72663 · Published 2026-09-28
Red Hat Enterprise Linux 10
- RHSA-2026:74001 · Published 2026-09-30
Red Hat Enterprise Linux 8
- RHSA-2026:72448 · Published 2026-09-28
Red Hat Enterprise Linux 9
- RHSA-2026:72663 · Published 2026-09-28
Rocky Linux 10
- RLSA-2026:74001 · Published 2026-10-01
Rocky Linux 8
- RLSA-2026:72448 · Published 2026-09-29
Rocky Linux 9
- RLSA-2026:72663 · Published 2026-09-30
SUSE Linux Enterprise Server 12 SP5
- SUSE-SU-2026:4806 · Published 2026-10-21
- SUSE-SU-2026:4615 · Published 2026-10-12
SUSE Linux Enterprise Server 15 SP5
- SUSE-SU-2026:4834 · Published 2026-10-21
- SUSE-SU-2026:4623 · Published 2026-10-12
SUSE Linux Enterprise Server 15 SP6
- SUSE-SU-2026:4834 · Published 2026-10-21
- SUSE-SU-2026:4623 · Published 2026-10-12
SUSE Linux Enterprise Server 15 SP7
- SUSE-SU-2026:4834 · Published 2026-10-21
- SUSE-SU-2026:4736 · Published 2026-10-19
- SUSE-SU-2026:4619 · Published 2026-10-12
SUSE Linux Enterprise Server 16
- SUSE-SU-2026:24260 · Published 2026-10-19

No fix evidence found:

Debian 11 (Bullseye)

Red Hat Enterprise Linux 7 (Extended Lifecycle Support)

Ubuntu 22.04 LTS (Jammy Jellyfish)

Ubuntu 24.04 LTS (Noble Numbat)

Ubuntu 25.04 (Plucky Puffin)

Ubuntu 25.10 (Questing Quokka)

Ubuntu 26.04 LTS (Resolute Raccoon)

Ubuntu 26.10 (Stonking Stingray)

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