CVE-2023-1206: A hash collision flaw was found in the IPv6 connection lookup table in the Linux kernel’s IPv6 functionality when a user makes a new kind of

Affected versions

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

• fedoraproject fedora38
• linux linux kernelbefore 6.5
• redhat enterprise linux8.0
• redhat enterprise linux9.0

Versions reported by the vendor

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

• n/a Kernel

  • kernel 6.5-rc1affected

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-2023-3389Jun 28, 2023 · Use after free in io_uring in the Linux Kernel
  31Monitor
• ← EarlierCVE-2023-28365Jun 30, 2023 · A backup file vulnerability found in UniFi applications (Version 7.3.83 and earlier) running on Linux operating systems allows application a
  36Monitor
• Later →CVE-2023-3338Jun 30, 2023 · Crash due to a null pointer dereference in the dn_nsp_send function
  29Monitor

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

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.