CVE-2009-3621: net/unix/af_unix.c in the Linux kernel 2.6.31.4 and earlier allows local users to cause a denial of service (system hang) by creating an abs

Affected versions

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

• canonical ubuntu linux6.06
• canonical ubuntu linux8.04
• canonical ubuntu linux8.10
• canonical ubuntu linux9.04
• canonical ubuntu linux9.10
• fedoraproject fedora10
• linux linux kernelup to 2.6.31.4 inclusive
• opensuse opensuse11.0
• opensuse opensuse11.2
• suse suse linux enterprise desktop10
• suse suse linux enterprise server10
• vmware esx4.0
• vmware vma4.0

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-2009-2910Oct 20, 2009 · arch/x86/ia32/ia32entry.S in the Linux kernel before 2.6.31.4 on the x86_64 platform does not clear certain kernel registers before a return
  8Monitor
• ← EarlierCVE-2009-3620Oct 22, 2009 · The ATI Rage 128 (aka r128) driver in the Linux kernel before 2.6.31-git11 does not properly verify Concurrent Command Engine (CCE) state in
  31Monitor
• Later →CVE-2009-3638Oct 29, 2009 · Integer overflow in the kvm_dev_ioctl_get_supported_cpuid function in arch/x86/kvm/x86.c in the KVM subsystem in the Linux kernel before 2.6
  28Monitor

Root cause

Code that parses nested structures sets no depth or size limit. A small input can turn into a disproportionate processing load.

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

1function expand(node) {2  return node.children.map(expand);3}

1const MAX_DEPTH = 32;2function expand(node, depth = 0) {3  if (depth > MAX_DEPTH) throw new Error("too deep");4  return node.children.map((c) => expand(c, depth + 1));5}

Attack context

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