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5.5
MEDIUM CVSS 3.1
CVE-2026-53012
nexthop: fix IPv6 route referencing IPv4 nexthop
Overview
Description

In the Linux kernel, the following vulnerability has been resolved: nexthop: fix IPv6 route referencing IPv4 nexthop syzbot reported a panic [1] [2]. When an IPv6 nexthop is replaced with an IPv4 nexthop, the has_v4 flag of all groups containing this nexthop is not updated. This is because nh_group_v4_update is only called when replacing AF_INET to AF_INET6, but the reverse direction (AF_INET6 to AF_INET) is missed. This allows a stale has_v4=false to bypass fib6_check_nexthop, causing IPv6 routes to be attached to groups that effectively contain only AF_INET members. Subsequent route lookups then call nexthop_fib6_nh() which returns NULL for the AF_INET member, leading to a NULL pointer dereference. Fix by calling nh_group_v4_update whenever the family changes, not just AF_INET to AF_INET6. Reproducer: # AF_INET6 blackhole ip -6 nexthop add id 1 blackhole # group with has_v4=false ip nexthop add id 100 group 1 # replace with AF_INET (no -6), has_v4 stays false ip nexthop replace id 1 blackhole # pass stale has_v4 check ip -6 route add 2001:db8::/64 nhid 100 # panic ping -6 2001:db8::1 [1] https://syzkaller.appspot.com/bug?id=e17283eb2f8dcf3dd9b47fe6f67a95f71faadad0 [2] https://syzkaller.appspot.com/bug?id=8699b6ae54c9f35837d925686208402949e12ef3

Details
INFO

Published Date :

June 24, 2026, 5:17 p.m.

Last Modified :

July 14, 2026, 5:40 p.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Impact
Affected Products

The following products are affected by CVE-2026-53012 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
: Total Affected Vendor : 1 | Products : 1
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update the kernel to fix a NULL pointer dereference due to incorrect flag updates.
  • Apply the Linux kernel patch.
  • Update the Linux kernel.
  • Verify flag updates in nexthop groups.
  • Test IPv6 route handling.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-53012.

URL Resource
https://git.kernel.org/stable/c/29c95185ba32b621fbc3800fb86e7dc3edf5c2be Patch
https://git.kernel.org/stable/c/613c8f4a501421dd258b07ea614205d4e16ec845 Patch
https://git.kernel.org/stable/c/6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8 Patch
https://git.kernel.org/stable/c/9c2d6770a5f4545a307eb66979bef7656a34d621 Patch
https://git.kernel.org/stable/c/aaac3bed034239e1d75732211d9b05f30b0b4f35 Patch
https://git.kernel.org/stable/c/ad85961004fd4bd2f31209ac4b07612c6cefb9e7 Patch
https://git.kernel.org/stable/c/b3b7e850e1541f0520c4a12ec884255c30427ff6 Patch
https://git.kernel.org/stable/c/ceffe81a0be92afc0cd1340bc8ca46559cce9bb4 Patch
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-53012 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-53012 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-53012 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-53012 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Jul. 14, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-476
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.2 up to (excluding) 6.6.141 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.7 up to (excluding) 6.12.91 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.18.33 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.0.10 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.16 up to (excluding) 6.1.175 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.15.209 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.3 up to (excluding) 5.10.258
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/29c95185ba32b621fbc3800fb86e7dc3edf5c2be Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/613c8f4a501421dd258b07ea614205d4e16ec845 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/9c2d6770a5f4545a307eb66979bef7656a34d621 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/aaac3bed034239e1d75732211d9b05f30b0b4f35 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/ad85961004fd4bd2f31209ac4b07612c6cefb9e7 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/b3b7e850e1541f0520c4a12ec884255c30427ff6 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/ceffe81a0be92afc0cd1340bc8ca46559cce9bb4 Types: Patch
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jun. 24, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '7bf4796dd09984ad1612877a82d0d139c70ae27f', 'lessThan': 'ceffe81a0be92afc0cd1340bc8ca46559cce9bb4', 'versionType': 'git'}, {'status': 'affected', 'version': '7bf4796dd09984ad1612877a82d0d139c70ae27f', 'lessThan': '9c2d6770a5f4545a307eb66979bef7656a34d621', 'versionType': 'git'}, {'status': 'affected', 'version': '7bf4796dd09984ad1612877a82d0d139c70ae27f', 'lessThan': '6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8', 'versionType': 'git'}, {'status': 'affected', 'version': '7bf4796dd09984ad1612877a82d0d139c70ae27f', 'lessThan': 'aaac3bed034239e1d75732211d9b05f30b0b4f35', 'versionType': 'git'}, {'status': 'affected', 'version': '7bf4796dd09984ad1612877a82d0d139c70ae27f', 'lessThan': 'ad85961004fd4bd2f31209ac4b07612c6cefb9e7', 'versionType': 'git'}, {'status': 'affected', 'version': '7bf4796dd09984ad1612877a82d0d139c70ae27f', 'lessThan': '613c8f4a501421dd258b07ea614205d4e16ec845', 'versionType': 'git'}, {'status': 'affected', 'version': '7bf4796dd09984ad1612877a82d0d139c70ae27f', 'lessThan': 'b3b7e850e1541f0520c4a12ec884255c30427ff6', 'versionType': 'git'}, {'status': 'affected', 'version': '7bf4796dd09984ad1612877a82d0d139c70ae27f', 'lessThan': '29c95185ba32b621fbc3800fb86e7dc3edf5c2be', 'versionType': 'git'}], 'programFiles': ['net/ipv4/nexthop.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.3'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.3', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.258', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.209', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.175', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.141', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.91', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.33', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.10', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/ipv4/nexthop.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: nexthop: fix IPv6 route referencing IPv4 nexthop syzbot reported a panic [1] [2]. When an IPv6 nexthop is replaced with an IPv4 nexthop, the has_v4 flag of all groups containing this nexthop is not updated. This is because nh_group_v4_update is only called when replacing AF_INET to AF_INET6, but the reverse direction (AF_INET6 to AF_INET) is missed. This allows a stale has_v4=false to bypass fib6_check_nexthop, causing IPv6 routes to be attached to groups that effectively contain only AF_INET members. Subsequent route lookups then call nexthop_fib6_nh() which returns NULL for the AF_INET member, leading to a NULL pointer dereference. Fix by calling nh_group_v4_update whenever the family changes, not just AF_INET to AF_INET6. Reproducer: # AF_INET6 blackhole ip -6 nexthop add id 1 blackhole # group with has_v4=false ip nexthop add id 100 group 1 # replace with AF_INET (no -6), has_v4 stays false ip nexthop replace id 1 blackhole # pass stale has_v4 check ip -6 route add 2001:db8::/64 nhid 100 # panic ping -6 2001:db8::1 [1] https://syzkaller.appspot.com/bug?id=e17283eb2f8dcf3dd9b47fe6f67a95f71faadad0 [2] https://syzkaller.appspot.com/bug?id=8699b6ae54c9f35837d925686208402949e12ef3
    Added Reference https://git.kernel.org/stable/c/29c95185ba32b621fbc3800fb86e7dc3edf5c2be
    Added Reference https://git.kernel.org/stable/c/613c8f4a501421dd258b07ea614205d4e16ec845
    Added Reference https://git.kernel.org/stable/c/6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8
    Added Reference https://git.kernel.org/stable/c/9c2d6770a5f4545a307eb66979bef7656a34d621
    Added Reference https://git.kernel.org/stable/c/aaac3bed034239e1d75732211d9b05f30b0b4f35
    Added Reference https://git.kernel.org/stable/c/ad85961004fd4bd2f31209ac4b07612c6cefb9e7
    Added Reference https://git.kernel.org/stable/c/b3b7e850e1541f0520c4a12ec884255c30427ff6
    Added Reference https://git.kernel.org/stable/c/ceffe81a0be92afc0cd1340bc8ca46559cce9bb4
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 5.5
Attack Vector
Attack Complexity
Privileges Required
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Scope
Confidentiality Impact
Integrity Impact
Availability Impact