CVE-2025-37823: net_sched: hfsc: Fix a potential UAF in hfsc_dequeue() too

Affected versions

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

• debian debian linux11.0
• linux linux kernel5.5 and later · before 5.10.237
• linux linux kernel5.11 and later · before 5.15.181
• linux linux kernel5.16 and later · before 6.1.136
• linux linux kernel6.2 and later · before 6.6.89
• linux linux kernel2.6.13 and later · before 5.4.293
• linux linux kernel6.13 and later · before 6.14.5
• linux linux kernel6.7 and later · before 6.12.26
• linux linux kernel2.6.12
• linux linux kernel6.15

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

  • 2.6.12affected
  • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 68f256305ceb426d545a0dc31f83c2ab1d211a1eaffected · git
  • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 2f46d14919c39528c6e540ebc43f90055993eedcaffected · git
  • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before da7936518996d290e2fcfcaf6cd7e15bfd87804aaffected · git
  • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 11bccb054c1462fb069219f8e98e97a5a730758eaffected · git
  • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 76c4c22c2437d3d3880efc0f62eca06ef078d290affected · git
  • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before c6f035044104c6ff656f4565cd22938dc892528caffected · git
  • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before c6936266f8bf98a53f28ef9a820e6a501e946d09affected · git
  • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 6ccbda44e2cc3d26fd22af54c650d6d5d801addfaffected · git
  • before 2.6.12not 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-2025-37820May 8, 2025 · xen-netfront: handle NULL returned by xdp_convert_buff_to_frame()
  22Monitor
• ← EarlierCVE-2025-37822May 8, 2025 · riscv: uprobes: Add missing fence.i after building the XOL buffer
  31Monitor
• Later →CVE-2025-37824May 8, 2025 · tipc: fix NULL pointer dereference in tipc_mon_reinit_self()
  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.