CVE-2026-46259: procfs: fix missing RCU protection when reading real_parent in do_task_stat()

Affected versions

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

• linux linux kernel2.6.26 and later · before 5.10.252
• linux linux kernel5.11 and later · before 5.15.202
• linux linux kernel5.16 and later · before 6.1.165
• linux linux kernel6.2 and later · before 6.6.128
• linux linux kernel6.7 and later · before 6.12.75
• linux linux kernel6.13 and later · before 6.18.14
• linux linux kernel6.19 and later · before 6.19.4

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

  • 2.6.26affected
  • 06fffb1267c9d986687b69d74a46ee332a50575e and later · before fefa0fcd78be465b7ad4c497fa6ec90d64194c04affected · git
  • 06fffb1267c9d986687b69d74a46ee332a50575e and later · before c93a33f28f915d446eea6fb3f0e1def0b3af1982affected · git
  • 06fffb1267c9d986687b69d74a46ee332a50575e and later · before 1c8dc5b5517546c68ffae40b948336122bb61306affected · git
  • 06fffb1267c9d986687b69d74a46ee332a50575e and later · before 0e64bd46a04a4fd61279aca9f53a664e9e5f7e7eaffected · git
  • 06fffb1267c9d986687b69d74a46ee332a50575e and later · before 73ec7c96601d61d52310c659145bb06d933a0fa6affected · git
  • 06fffb1267c9d986687b69d74a46ee332a50575e and later · before 4f9ae386861e280b7631ca252f798d25575627eeaffected · git
  • 06fffb1267c9d986687b69d74a46ee332a50575e and later · before dd8b13cb4ff1a4545a214ed897fdf2bc341155b6affected · git
  • 06fffb1267c9d986687b69d74a46ee332a50575e and later · before 76149d53502cf17ef3ae454ff384551236fba867affected · git
  • before 2.6.26not 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-2026-46254Jun 3, 2026 · AppArmor: Allow apparmor to handle unaligned dfa tables
  22Monitor
• ← EarlierCVE-2026-46256Jun 3, 2026 · NFS/localio: prevent direct reclaim recursion into NFS via nfs_writepages
  22Monitor
• Later →CVE-2026-46263Jun 3, 2026 · drm/amd/display: Fix out-of-bounds stream encoder index v3
  31Monitor

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.