CVE-2025-38732

MEDIUM EPSS 5.6%
Published Sep 5, 20259mo ago · Modified Jun 17, 20261w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Sep 5, 2025 9mo ago
Last Modified Jun 17, 2026 1w ago

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_reject: don't leak dst refcount for loopback packets recent patches to add a WARN() when replacing skb dst entry found an old bug: WARNING: include/linux/skbuff.h:1165 skb_dst_check_unset include/linux/skbuff.h:1164 [inline] WARNING: include/linux/skbuff.h:1165 skb_dst_set include/linux/skbuff.h:1210 [inline] WARNING: include/linux/skbuff.h:1165 nf_reject_fill_skb_dst+0x2a4/0x330 net/ipv4/netfilter/nf_reject_ipv4.c:234 [..] Call Trace: nf_send_unreach+0x17b/0x6e0 net/ipv4/netfilter/nf_reject_ipv4.c:325 nft_reject_inet_eval+0x4bc/0x690 net/netfilter/nft_reject_inet.c:27 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] .. This is because blamed commit forgot about loopback packets. Such packets already have a dst_entry attached, even at PRE_ROUTING stage. Instead of checking hook just check if the skb already has a route attached to it.

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
5.6% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Affected Products 9

VendorProductVersionRange
linuxlinux_kernel*≥5.9  –  <5.10.241
linuxlinux_kernel*≥5.11  –  <5.15.190
linuxlinux_kernel*≥5.16  –  <6.1.149
linuxlinux_kernel*≥6.2  –  <6.6.103
linuxlinux_kernel*≥6.7  –  <6.12.44
linuxlinux_kernel*≥6.13  –  <6.16.4
linuxlinux_kernel6.17any
linuxlinux_kernel6.17any
debiandebian_linux11.0any

References 10

  • cert-portal.siemens.com https://cert-portal.siemens.com/productcert/html/ssa-032379.html
  • git.kernel.org https://git.kernel.org/stable/c/51e8531371f90bee742c63775c9a568e5d6bf3c5
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/7b8b503c06274ef3c6c1a107743f1ec0d0a53ef8
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/82ef97abf22790182f7d433c74960dfd61b99c33
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/91a79b792204313153e1bdbbe5acbfc28903b3a5
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a0a3ace2a57887dac1e7c9a724846040c3e31868
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b32e1590a8d22cf7d7f965e46d5576051acf8e42
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b7a885ba25960c91db237c3f83b4285156789bce
    Patch
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
    Mailing ListThird Party Advisory
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
    Mailing ListThird Party Advisory

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/51e8531371f90bee742c63775c9a568e5d6bf3c5
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/7b8b503c06274ef3c6c1a107743f1ec0d0a53ef8
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/82ef97abf22790182f7d433c74960dfd61b99c33
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/91a79b792204313153e1bdbbe5acbfc28903b3a5
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a0a3ace2a57887dac1e7c9a724846040c3e31868
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b32e1590a8d22cf7d7f965e46d5576051acf8e42
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b7a885ba25960c91db237c3f83b4285156789bce
    Patch