CVE intelligence and bounded remediation

CVE-2023-53439 — Linux Linux Kernel security vulnerability

Medium CVSS 5.5

In the Linux kernel, the following vulnerability has been resolved: net: skb_partial_csum_set() fix against transport header magic value skb->transport_header uses the special 0xFFFF value to mark if the transport header was set or not. We must prevent callers to accidentaly set skb->transport_header to 0xFFFF. Note that only fuzzers can possibly do this today. syzbot reported: WARNING: CPU: 0 PID: 2340 at include/linux/skbuff.h:2847 skb_transport_offset include/linux/skbuff.h:2956 [inline] WARNING: CPU: 0 PID: 2340 at include/linux/skbuff.h:2847 virtio_net_hdr_to_skb+0xbcc/0x10c0 include/linux/virtio_net.h:103 Modules linked in: CPU: 0 PID: 2340 Comm: syz-executor.0 Not tainted 6.3.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:skb_transport_header include/linux/skbuff.h:2847 [inline] RIP: 0010:skb_transport_offset include/linux/skbuff.h:2956 [inline] RIP: 0010:virtio_net_hdr_to_skb+0xbcc/0x10c0 include/linux/virtio_net.h:103 Code: 41 39 df 0f 82 c3 04 00 00 48 8b 7c 24 10 44 89 e6 e8 08 6e 59 ff 48 85 c0 74 54 e8 ce 36 7e fc e9 37 f8 ff ff e8 c4 36 7e fc <0f> 0b e9 93 f8 ff ff 44 89 f7 44 89 e6 e8 32 38 7e fc 45…

Severity
Medium
CVSS
5.5 (3.1)
Published
2025-09-18
CISA KEV
Not currently listed
Ecosystem
linux/kernel
Weaknesses
CWE-401

Affected products

  • linux / linux_kernel
  • linux / linux_kernel / 6.4

Showing 2 representative product identities from 3 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Resource exhaustion and denial of service

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

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