Use-after-free in Linux kernel's net/sched: cls_u32 component

Affected versions

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

• debian debian linux10.0
• debian debian linux11.0
• linux linux kernel4.20 and later · before 5.4.248
• linux linux kernel5.5 and later · before 5.10.185
• linux linux kernel5.11 and later · before 5.15.118
• linux linux kernel4.14 and later · before 4.14.322
• linux linux kernel6.2 and later · before 6.3.9
• linux linux kernel5.16 and later · before 6.1.35
• linux linux kernel4.15 and later · before 4.19.291
• linux linux kernel6.4

Versions reported by the vendor

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

• Linux Kernel

  • 6.4.0, 04c55383fa5689357bcdd2c8036725a55ed632bcnot affected
  • 4.14.0 and later · before 4.14.322affected · semver
  • 4.15.0 and later · before 4.19.291affected · semver
  • 4.20.0 and later · before 5.4.248affected · semver
  • 5.5.0 and later · before 5.10.185affected · semver
  • 5.11.0 and later · before 5.15.118affected · semver
  • 5.16.0 and later · before 6.1.35affected · semver
  • 6.2.0 and later · before 6.3.9affected · 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-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
• CVE-2016-5195Race condition in mm/gup.c in the Linux kernel 2.x through 4.x before 4.8.3 allows local users to gain privileges by leveraging incorrect haKEV
  83Now

Published before and after this one in the same product

• ← EarlierCVE-2023-0160Jul 18, 2023 · Possibility of deadlock in libbpf function sock_hash_delete_elem
  22Monitor
• ← EarlierCVE-2023-3776Jul 21, 2023 · Use-after-free in Linux kernel's net/sched: cls_fw component
  31Monitor
• Later →CVE-2023-3610Jul 21, 2023 · Use-after-free in Linux kernel's netfilter: nf_tables component
  31Monitor

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

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.