Not yet scoredPublished Sep 3, 2026

CVE-2026-80733net: remove WARN_ON_ONCE() from sk_mc_loop()

Updated under an hour ago (Oct 26, 2026, 2:00 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: net: remove WARN_ON_ONCE() from sk_mc_loop() sk_mc_loop() can be called for sockets that are neither AF_INET nor AF_INET6 (e.g. AF_PACKET sockets when sending packets via raw/packet socket over virtual devices such as VRF or ipvlan). In such cases, sk_family is not AF_INET/AF_INET6 and sk_mc_loop() falls through the switch statement and triggers WARN_ON_ONCE(1). Non-INET sockets do not support IP_MULTICAST_LOOP or IPV6_MULTICAST_LOOP options, so loopback should default to true without generating a warning.

CVSS: Not yet scored
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Received
Record last updated: Sep 3, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from f60e5990d9c1424af9dbca60a23ba2a1c7c1ce90 before 97133c4d42654578fab95abe47359ebe784dde18; from f60e5990d9c1424af9dbca60a23ba2a1c7c1ce90 before f625c742b33dc137c209dd13d1c5f12b1c18d71c; from f60e5990d9c1424af9dbca60a23ba2a1c7c1ce90 before ad7fa2f411cb30f63d6725f111be134064cdb718; from f60e5990d9c1424af9dbca60a23ba2a1c7c1ce90 before d2adc4e80b29e58b5162ae09f0f657a215806c8c; from f60e5990d9c1424af9dbca60a23ba2a1c7c1ce90 before ad7dbb1d14b1b4406eca8ef9478e8de312ba0cfe; from f60e5990d9c1424af9dbca60a23ba2a1c7c1ce90 before c8f256dc849205ccb2bd78bd99a3497b972b44e0; from f60e5990d9c1424af9dbca60a23ba2a1c7c1ce90 before 0d75f2c1d0764efa756ad9c1e078d8c09ea8fc1f; from f60e5990d9c1424af9dbca60a23ba2a1c7c1ce90 before b8a39a09ae4eaae04309e1e38ed6a1101d967496; and 6 more ranges	CNA record

References

References

https://git.kernel.org/stable/c/97133c4d42654578fab95abe47359ebe784dde18
https://git.kernel.org/stable/c/f625c742b33dc137c209dd13d1c5f12b1c18d71c
https://git.kernel.org/stable/c/ad7fa2f411cb30f63d6725f111be134064cdb718
https://git.kernel.org/stable/c/d2adc4e80b29e58b5162ae09f0f657a215806c8c
https://git.kernel.org/stable/c/ad7dbb1d14b1b4406eca8ef9478e8de312ba0cfe
https://git.kernel.org/stable/c/c8f256dc849205ccb2bd78bd99a3497b972b44e0
https://git.kernel.org/stable/c/0d75f2c1d0764efa756ad9c1e078d8c09ea8fc1f
https://git.kernel.org/stable/c/b8a39a09ae4eaae04309e1e38ed6a1101d967496

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.