In the Linux kernel, the following vulnerability has been resolved: ipv4: fib: Don't ignore error route in local/main tables. When CONFIG_IP_MULTIPLE_TABLES is enabled but no rule is added, fib_lookup() performs route lookup directly on two tables. Since the first lookup does not properly bail out, the result of an error route in the merged local/main table could be overwritten by another route in the default table: # unshare -n # ip link set lo up # ip route add 192.168.0.0/24 dev lo table 253 # ip route add unreachable 192.168.0.0/24 # ip route get 192.168.0.1 192.168.0.1 dev lo table default uid 0 cache <local> Once a random rule is added, the error route is respected: # ip rule add table 0 # ip rule del table 0 # ip route get 192.168.0.1 RTNETLINK answers: No route to host Let's fix the inconsistent behaviour.

Metrics

No CVSS v4.0

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.0022.

Key SSVC decision points have not yet been added.

Affected Vendors & Products

Vendors Products
Linux
  • Linux Kernel

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors Products
References
Link Providers
https://git.kernel.org/stable/c/49eaf1403201357762d745a35882fb734107d763 cve-icon cve-icon
https://git.kernel.org/stable/c/5ae18d87a45698e8244d0fcba64c658c35a7dd3d cve-icon cve-icon
https://git.kernel.org/stable/c/828fad4fd418bcdb9f5d66fec0d184c52a85ec31 cve-icon cve-icon
https://git.kernel.org/stable/c/9127589aabdee588278e8d0d0bd3709a760a92c8 cve-icon cve-icon
https://git.kernel.org/stable/c/a29e95fbc51e8a1b932773fd0e259b2080881443 cve-icon cve-icon
https://git.kernel.org/stable/c/a668fa160247d7bbe921548cb845f607b8b9305f cve-icon cve-icon
https://git.kernel.org/stable/c/b72f0db64205d9ce462038ba995d5d31eff32dc1 cve-icon cve-icon
https://git.kernel.org/stable/c/fd25996f57a95d56bc568c89b4921edcf334b7d8 cve-icon cve-icon
History

Sat, 15 Aug 2026 12:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-640

Sat, 15 Aug 2026 06:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: ipv4: fib: Don't ignore error route in local/main tables. When CONFIG_IP_MULTIPLE_TABLES is enabled but no rule is added, fib_lookup() performs route lookup directly on two tables. Since the first lookup does not properly bail out, the result of an error route in the merged local/main table could be overwritten by another route in the default table: # unshare -n # ip link set lo up # ip route add 192.168.0.0/24 dev lo table 253 # ip route add unreachable 192.168.0.0/24 # ip route get 192.168.0.1 192.168.0.1 dev lo table default uid 0 cache <local> Once a random rule is added, the error route is respected: # ip rule add table 0 # ip rule del table 0 # ip route get 192.168.0.1 RTNETLINK answers: No route to host Let's fix the inconsistent behaviour.
Title ipv4: fib: Don't ignore error route in local/main tables.
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-08-15T05:56:40.466Z

Reserved: 2026-08-09T03:40:39.927Z

Link: CVE-2026-72421

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-15T06:22:15.867

Modified: 2026-08-15T06:22:15.867

Link: CVE-2026-72421

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-15T12:00:05Z