CVE-2026-93167
Vulnérabilité non évaluée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: csky: Fix a4/a5 restoration in syscall trace path The syscall trace path reloads syscall arguments from pt_regs before calling the syscall handler. On C-SKY ABIv2, the 5th and 6th syscall arguments are prepared as stack arguments before invoking syscallid. The current code adjusts sp before loading LSAVE_A4 and LSAVE_A5. Since those offsets are relative to the original pt_regs base, loading them after changing sp fetches the wrong slots. As a result, traced syscalls that use the 5th or 6th argument may receive corrupted arguments. This is visible with mmap2(), which takes six arguments. A small PTRACE_SYSCALL reproducer opens a file and maps one page with: mmap(NULL, 4096, PROT_READ | PROT_EXEC, MAP_PRIVATE, fd, 0) Before the fix, the traced child fails the mmap and exits with 12. After the fix, the mapping succeeds and the child exits with 0. Fix the trace path by loading a4/a5 from pt_regs before changing sp. Tested on: ck860f, linux-4.19.15, C-SKY abiv2
Gravité et risque d'exploitation
CVE-2026-93167 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 0.22 %, ce qui la place devant 11.7 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions <e9ae8e86eed68bea5d2670eadf61938a43bd2263, <abb81e5ce7d995baa41556b8125fa59e28ba3be8, <=6.1.*, <=6.12.*, 3a5837c692918c229baf63fe7950965d27c48ac2, 5.15.221, 5.10.270, 0, 6.1.188, 108681048cf728a8570e036c34ebd7daa43133b4, 6.18.52, 5.4.47, <343aa5275484d627c921a42e8e115cae366be5de, <5.7, <=5.10.*, <=6.6.*, <31c81b376e5f058c7f2c94f69719cf7caec2fc3f, 6.6.157, <a776afa89424570bfa637ebf812ca281a5732904, 7.2.6, <5.5, <=6.18.*, <863fa63fd1491f201ac819f805a8db98d2a32c3d, <e71a3dc5b8d2ea4d9cfbdb135d6b7777de84212e, 5.6.19, 6.12.110, <=7.2.*, e0bbb53843b5fdfe464b099217e3b9d97e8a75d7, 5.7, <=*, <64e3ec7a71d3b715e2567f19f64207f04999bb0c, <=5.15.*, 7.3) 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/e9ae8e86eed68bea5d2670eadf61938a43bd2263
- https://git.kernel.org/stable/c/64e3ec7a71d3b715e2567f19f64207f04999bb0c
- https://git.kernel.org/stable/c/863fa63fd1491f201ac819f805a8db98d2a32c3d
- https://git.kernel.org/stable/c/e71a3dc5b8d2ea4d9cfbdb135d6b7777de84212e
- https://git.kernel.org/stable/c/31c81b376e5f058c7f2c94f69719cf7caec2fc3f
- https://git.kernel.org/stable/c/a776afa89424570bfa637ebf812ca281a5732904
- https://git.kernel.org/stable/c/343aa5275484d627c921a42e8e115cae366be5de
- https://git.kernel.org/stable/c/abb81e5ce7d995baa41556b8125fa59e28ba3be8