CVE-2025-37929: Debian Linux

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: arm64: errata: Add missing sentinels to Spectre-BHB MIDR arrays Commit a5951389e58d ("arm64: errata: Add newer ARM cores to the spectre_bhb_loop_affected() lists") added some additional CPUs to the Spectre-BHB workaround, including some new arrays for designs that require new 'k' values for the workaround to be effective. Unfortunately, the new arrays omitted the sentinel entry and so is_midr_in_range_list() will walk off the end when it doesn't find a match. With UBSAN enabled, this leads to a crash during boot when is_midr_in_range_list() is inlined (which was more common prior to c8c2647e69be ("arm64: Make  _midr_in_range_list() an exported function")): | Internal error: aarch64 BRK: 00000000f2000001 [#1] PREEMPT SMP | pstate: 804000c5 (Nzcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : spectre_bhb_loop_affected+0x28/0x30 | lr : is_spectre_bhb_affected+0x170/0x190 | [...] | Call trace: | spectre_bhb_loop_affected+0x28/0x30 | update_cpu_capabilities+0xc0/0x184 | init_cpu_features+0x188/0x1a4 | cpuinfo_store_boot_cpu+0x4c/0x60 | smp_prepare_boot_cpu+0x38/0x54 | start_kernel+0x8c/0x478 | __primary_switched+0xc8/0xd4 | Code: 6b09011f 54000061 52801080 d65f03c0 (d4200020) | ---[ end trace 0000000000000000 ]--- | Kernel panic - not syncing: aarch64 BRK: Fatal exception Add the missing sentinel entries.

Affected products

• Debian Debian Linux: version 11.0 only
• Linux Linux Kernel: from 6.1.135, before 6.1.138 (fixed in 6.1.138); from 6.6.88, before 6.6.90 (fixed in 6.6.90); from 6.12.24, before 6.12.28 (fixed in 6.12.28); from 6.13.12, before 6.14 (fixed in 6.14); from 6.14.3, before 6.14.6 (fixed in 6.14.6); version 5.15.181 only; …

Published 2025-05-20. Last modified 2026-06-17.