CVE-2026-64508

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Support for hardening against JIT spraying The BPF JIT allocator packs many small programs into larger executable allocations and reuses space within those allocations as programs are loaded and freed. When fresh code is written into space that a previous program occupied, an indirect jump into the new program can reuse a branch prediction left behind by the old one. Flush the indirect branch predictors before reusing JIT memory so that indirect jumps into a newly written program don't reuse predictions from an old program that occupied the same space. Introduce bpf_arch_pred_flush_enabled static key and bpf_arch_pred_flush static call for flushing the branch predictors on JIT memory reuse. Architectures that need a flush, can update it to a predictor flush function. By default, its a NOP and does not emit any CALL. Allocations larger than a pack are not covered by this flush. That is safe because cBPF programs (the unprivileged attack surface) are bounded well below a pack size. Issue a warning if this assumption is ever violated while the flush is active.

Gravité et risque d'exploitation

CVE-2026-64508 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 0.19 %, ce qui la place devant 8.0 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.1.*, <=6.12.*, <1fbafd5235ca897b322161659ebe8ba651b00b3b, 5.18, 6.18.39, <96cce16e26dd02a8678f1e87f88a4b5cdb63b995, 0, <6e52c240c43a601b681e3a4e58fc5685114d4726, 7.1.4, <=7.1.*, <5.18, 6.12.97, <=6.6.*, 6.1.183, <eed774da601268dae674e14d54a15e3624691f52, <=6.18.*, 6.6.145, <7a6c171c6a1ac6d1509752dac131d941a3de0b37, <=*, 57631054fae6dcc9c892ae6310b58bbb6f6e5048, <8ff183ee4d8c452960df58175a094828c0513b2e, 7.2) 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.

Références

• https://git.kernel.org/stable/c/1fbafd5235ca897b322161659ebe8ba651b00b3b
• https://git.kernel.org/stable/c/6e52c240c43a601b681e3a4e58fc5685114d4726
• https://git.kernel.org/stable/c/eed774da601268dae674e14d54a15e3624691f52
• https://git.kernel.org/stable/c/8ff183ee4d8c452960df58175a094828c0513b2e
• https://git.kernel.org/stable/c/7a6c171c6a1ac6d1509752dac131d941a3de0b37
• https://git.kernel.org/stable/c/96cce16e26dd02a8678f1e87f88a4b5cdb63b995