# CVE-2026-31637: rxrpc: reject undecryptable rxkad response tickets CVE-2026-31637 is fixed in 37 products on 1 platform, first by ALAS2023-2026-1695, released May 8, 2026. It is not reported as exploited. Patch Radar priority: High. - Web page: https://patchblox.com/security/cve/CVE-2026-31637 - Priority: High - CVSS: 9.8 (Moderate) - EPSS: 0.0059 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: Apr 24, 2026 - Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-31637 ## Description In the Linux kernel, the following vulnerability has been resolved: rxrpc: reject undecryptable rxkad response tickets rxkad_decrypt_ticket() decrypts the RXKAD response ticket and then parses the buffer as plaintext without checking whether crypto_skcipher_decrypt() succeeded. A malformed RESPONSE can therefore use a non-block-aligned ticket length, make the decrypt operation fail, and still drive the ticket parser with attacker-controlled bytes. Check the decrypt result and abort the connection with RXKADBADTICKET when ticket decryption fails. ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Linux | bpftool6.12 amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | bpftool6.12-debuginfo amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | bpftool6.18 amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | bpftool6.18-debuginfo amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel-livepatch-6.12.83-113.160 amzn 2023 | 1:1.0-0.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel-livepatch-6.18.25-55.108 amzn 2023 | 1:1.0-0.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.12 amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.12-debuginfo amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.12-debuginfo-common-aarch64 amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.12-debuginfo-common-x86_64 amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.12-devel amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.12-headers amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.12-modules-extra amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.12-modules-extra-common amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.12-tools amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.12-tools-debuginfo amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.12-tools-devel amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | kernel6.18 amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.18-debuginfo amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.18-debuginfo-common-aarch64 amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.18-debuginfo-common-x86_64 amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.18-devel amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.18-headers amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.18-modules-extra amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.18-modules-extra-common amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.18-tools amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.18-tools-debuginfo amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | kernel6.18-tools-devel amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | linux Debian 12.15 (bookworm) | 6.1.176-1 | [DEBIAN-CVE-2026-31637](https://patchblox.com/security/data/fix/linux/debian-cve-2026-31637.md) | May 15, 2026 | | Linux | linux Debian 13.5 (trixie) | 6.12.85-1 | [DEBIAN-CVE-2026-31637](https://patchblox.com/security/data/fix/linux/debian-cve-2026-31637.md) | May 15, 2026 | | Linux | linux Debian 14 | 6.19.13-1 | [DEBIAN-CVE-2026-31637](https://patchblox.com/security/data/fix/linux/debian-cve-2026-31637.md) | May 15, 2026 | | Linux | perf6.12 amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | perf6.12-debuginfo amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | perf6.18 amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | perf6.18-debuginfo amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | python3-perf6.12 amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | python3-perf6.12-debuginfo amzn 2023 | 1:6.12.83-113.160.amzn2023 | [ALAS2023-2026-1695](https://patchblox.com/security/data/fix/linux/alas2023-2026-1695.md) | May 8, 2026 | | Linux | python3-perf6.18 amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | | Linux | python3-perf6.18-debuginfo amzn 2023 | 1:6.18.25-55.108.amzn2023 | [ALAS2023-2026-1693](https://patchblox.com/security/data/fix/linux/alas2023-2026-1693.md) | May 8, 2026 | --- Data as of 2026-11-09T07:25:28Z UTC. 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