CVE-2026-18040

Severity: Moderate

Published: 2026-10-03

In Bouncy Castle for Java before 1.86, HQC leaked secret-derived data through two side channels: its GF(2^8) arithmetic used lookup tables indexed by field elements, making the cache line touched...

Exploit evidence

No public exploit evidence reported by NVD

Last checked: 2026-10-15 14:42 UTC

No exploitation evidence · CISA Coordinator (Assessed 2026-10-05 16:00 UTC)

NVD evidence for CVE-2026-18040 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: 2026-10-22 06:25 UTC

Fixed in:

SUSE Linux Enterprise Server 15 SP5
- SUSE-SU-2026:4797 · Published 2026-10-21
SUSE Linux Enterprise Server 15 SP6
- SUSE-SU-2026:4797 · Published 2026-10-21
SUSE Linux Enterprise Server 15 SP7
- SUSE-SU-2026:4797 · Published 2026-10-21

No fix evidence found:

AlmaLinux 10

AlmaLinux 8

AlmaLinux 9

Debian 11 (Bullseye)

Debian 12 (Bookworm)

Debian 13 (Trixie)

Oracle Linux 10

Oracle Linux 8

Oracle Linux 9

Red Hat Enterprise Linux 10

Red Hat Enterprise Linux 7 (Extended Lifecycle Support)

Red Hat Enterprise Linux 8

Red Hat Enterprise Linux 9

Rocky Linux 10

Rocky Linux 8

Rocky Linux 9

SUSE Linux Enterprise Server 12 SP5

SUSE Linux Enterprise Server 16

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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