Vulnerability in Linux kernel (CVE-2026-89815)
Summary
Vulnerability in Linux kernel (CVE-2026-89815). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
drm/ttm: Drop tt->restore after successful restore
ttm_pool_restore_and_alloc() can successfully complete the restore
process via ttm_pool_restore_commit(), but tt->restore is not dropped
afterward. As a result, subsequent backup/restore flows observe what
appears to be a completed restore, while in reality shmem handles are
still installed in tt->pages, leading to the stack trace below.
Fix this by freeing and dropping tt->restore in
ttm_pool_restore_and_alloc() upon successful completion of the restore.
20545 [ 309.784531] RIP: 0010:sg_alloc_append_table_from_pages+0x38c/0x490
20547 [ 309.809570] RSP: 0018:ffffc9000623b838 EFLAGS: 00010206
20548 [ 309.814827] RAX: 0000000000001000 RBX: ffff88816e42a160 RCX: 0000000000000000
20549 [ 309.821986] RDX: 0000000000002000 RSI: 0000000000000003 RDI: 0000000000001000
20550 [ 309.829147] RBP: ffff88816e42a168 R08: 0000000000000002 R09: 000000007ffff000
20551 [ 309.836310] R10: ffffc9000623b928 R11: 0000000000000000 R12: 000000007ffff000
20552 [ 309.843471] R13: ffff88815ba5a100 R14: 0000000000000000 R15: 0000000000000001
20553 [ 309.850634] FS: 00007f9ff305e700(0000) GS:ffff888276c94000(0000) knlGS:0000000000000000
20554 [ 309.858749] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
20555 [ 309.864519] CR2: 00007f9fca701000 CR3: 00000001565e2005 CR4: 0000000008f70ef0
20556 [ 309.871678] PKRU: 55555558
20557 [ 309.874403] Call Trace:
20558 [ 309.876…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-89815 has been found in Linux kernel.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-89815" on the vendor's site.
CVE-2026-89815 (Linux kernel) — CVSS v3 7.8
Attack vector: local / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (unclassified) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com