CVE-2026-23052
Vulnérabilité non évaluée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: ftrace: Do not over-allocate ftrace memory The pg_remaining calculation in ftrace_process_locs() assumes that ENTRIES_PER_PAGE multiplied by 2^order equals the actual capacity of the allocated page group. However, ENTRIES_PER_PAGE is PAGE_SIZE / ENTRY_SIZE (integer division). When PAGE_SIZE is not a multiple of ENTRY_SIZE (e.g. 4096 / 24 = 170 with remainder 16), high-order allocations (like 256 pages) have significantly more capacity than 256 * 170. This leads to pg_remaining being underestimated, which in turn makes skip (derived from skipped - pg_remaining) larger than expected, causing the WARN(skip != remaining) to trigger. Extra allocated pages for ftrace: 2 with 654 skipped WARNING: CPU: 0 PID: 0 at kernel/trace/ftrace.c:7295 ftrace_process_locs+0x5bf/0x5e0 A similar problem in ftrace_allocate_records() can result in allocating too many pages. This can trigger the second warning in ftrace_process_locs(). Extra allocated pages for ftrace WARNING: CPU: 0 PID: 0 at kernel/trace/ftrace.c:7276 ftrace_process_locs+0x548/0x580 Use the actual capacity of a page group to determine the number of pages to allocate. Have ftrace_allocate_pages() return the number of allocated pages to avoid having to calculate it. Use the actual page group capacity when validating the number of unused pages due to skipped entries. Drop the definition of ENTRIES_PER_PAGE since it is no longer used.
Gravité et risque d'exploitation
CVE-2026-23052 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.20 %, ce qui la place devant 8.7 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions 4a3efc6baff931da9a85c6d2e42c87bd9a827399, <=*, 6.19, 6.15, <6.15, <=6.18.*, <9aef476717994e96dadfb359641c4b82b521aa36, <be55257fab181b93af38f8c4b1b3cb453a78d742, 0, 6.18.7, <bf802b936a7b269917e4dc233e49f6a928db8286, <23936d19e4383c8dfb03931f032473d4baf92533, 2a6ce8bddd8aafa61aaa705e76eae810f22429be, dc06779d338de4e5a46166a93ec124222e09f40a) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.
