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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-74657 Detail

Description

In the Linux kernel, the following vulnerability has been resolved: ipv4: Fix fib_nlmsg_size() for RTA_VIA nexthops fib_nlmsg_size() still estimates nexthop space as if every gateway is encoded as an IPv4 RTA_GATEWAY attribute. IPv4 routes can also carry an IPv6 gateway, which fib_nexthop_info() dumps as RTA_VIA. As a result, route notifications can allocate an skb that is too small. fib_dump_info() then fails with -EMSGSIZE and rtmsg_fib() hits the WARN_ON() that marks such failures as a fib_nlmsg_size() bug. With panic_on_warn set, this becomes a kernel panic. Mirror the actual nexthop dump layout in fib_nlmsg_size(): account for IPv6 nexthop gateways dumped as RTA_VIA, for the no-header rtnexthop layout used inside RTA_MULTIPATH, and for RTA_FLOW only when it is actually present.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

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URL Source(s) Tag(s)
https://git.kernel.org/stable/c/0f0ca602941d0a81ae9514943ca06c55159c6385 kernel.org
https://git.kernel.org/stable/c/4a5dfbae5179f6574695012a980476254df2d295 kernel.org
https://git.kernel.org/stable/c/4ff9548d84945d2cbf9e4c207288063a200ea397 kernel.org
https://git.kernel.org/stable/c/5307a53599fa762c06e475ee4a375252074fd324 kernel.org
https://git.kernel.org/stable/c/7f80ad373ce4a7af5367ff273cea0f16e91387f3 kernel.org
https://git.kernel.org/stable/c/9b22f13524fa0de0d963bbd3002df6c28bae3395 kernel.org
https://git.kernel.org/stable/c/a59edda6eda1252340354322d8ab318b2e9052fb kernel.org

Weakness Enumeration

CWE-ID CWE Name Source

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-74657
NVD Published Date:
08/22/2026
NVD Last Modified:
08/22/2026
Source:
kernel.org