CVE-2026-23401: KVM: x86/mmu: Drop/zap existing present SPTE even when creating an MMIO SPTE

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

• linux linux kernel5.13.1 and later · before 5.15.203
• linux linux kernel5.16 and later · before 6.1.168
• linux linux kernel6.2 and later · before 6.6.131
• linux linux kernel6.7 and later · before 6.12.80
• linux linux kernel6.13 and later · before 6.18.21
• linux linux kernel6.19 and later · before 6.19.11
• linux linux kernel5.13
• linux linux kernel7.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

• Linux Linux

  • 5.13affected
  • a54aa15c6bda3ca7e2f9e040ba968a1da303e24f and later · before 20656cd1f243d3a154aac5dd1b823110b6906fe1affected · git
  • a54aa15c6bda3ca7e2f9e040ba968a1da303e24f and later · before ed5909992f344a7d3f4024261e9f751d9618a27daffected · git
  • a54aa15c6bda3ca7e2f9e040ba968a1da303e24f and later · before fd28c5618699180cd69619801e9ae6a5266c0a22affected · git
  • a54aa15c6bda3ca7e2f9e040ba968a1da303e24f and later · before 459158151a158a6703b49f3c9de0e536d8bd553faffected · git
  • a54aa15c6bda3ca7e2f9e040ba968a1da303e24f and later · before 695320de6eadb75aaed8be1787c4ce4c189e4c7baffected · git
  • a54aa15c6bda3ca7e2f9e040ba968a1da303e24f and later · before bce7fe59d43531623f3e43779127bfb33804925daffected · git
  • a54aa15c6bda3ca7e2f9e040ba968a1da303e24f and later · before aad885e774966e97b675dfe928da164214a71605affected · git
  • before 5.13not affected · semver
  • 5.15.203 and later · up to and including 5.15.*not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Other highest-scoring records for the same primary product.

• CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
  90Now
• CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
  89Now
• CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
  85Now

Published before and after this one in the same product

• ← EarlierCVE-2026-23399Mar 28, 2026 · nf_tables: nft_dynset: fix possible stateful expression memleak in error path
  22Monitor
• ← EarlierCVE-2026-23400Mar 29, 2026 · rust_binder: call set_notification_done() without proc lock
  22Monitor
• Later →CVE-2026-23402Apr 1, 2026 · KVM: x86/mmu: Only WARN in direct MMUs when overwriting shadow-present SPTE
  22Monitor

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

1free(dev->buf);2/* ... another thread is still running ... */3process(dev->buf);

1lock(&dev->lock);2free(dev->buf);3dev->buf = NULL;4unlock(&dev->lock);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.