by Kastro
Paper/Archive/CVE-2026-46266

CVE-2026-46266

Linux Linux — inet: RAW sockets using IPPROTO_RAW MUST drop incoming ICMP

EPSS 0.5%CVSS 9.1
critical.is priorityof 100
35
CVSS 9.1 (CNA)9.1 / 10 × 3027.3Not in CISA KEV+300.0EPSS percentile 40.2.402 × 208.0No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

In the Linux kernel, the following vulnerability has been resolved: inet: RAW sockets using IPPROTO_RAW MUST drop incoming ICMP Yizhou Zhao reported that simply having one RAW socket on protocol IPPROTO_RAW (255) was dangerous. socket(AF_INET, SOCK_RAW, 255); A malicious incoming ICMP packet can set the protocol field to 255 and match this socket, leading to FNHE cache changes. inner = IP(src="192.168.2.1", dst="8.8.8.8", proto=255)/Raw("TEST") pkt = IP(src="192.168.1.1", dst="192.168.2.1")/ICMP(type=3, code=4, nexthopmtu=576)/inner "man 7 raw" states: A protocol of IPPROTO_RAW implies enabled IP_HDRINCL and is able to send any IP protocol that is specified in the passed header. Receiving of all IP protocols via IPPROTO_RAW is not possible using raw sockets. Make sure we drop these malicious packets.

Affected

ProductAffectedFixed inSource
Linux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 47276297140ee6712646f9b19fb04fe26daedd0147276297140ee6712646f9b19fb04fe26daedd01CNA
Linux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < db76b75ede3810e7cf9cfea5067d4f3e0993768bdb76b75ede3810e7cf9cfea5067d4f3e0993768bCNA
Linux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 19e42490c89bac9a388f28179e66bebbef350f9919e42490c89bac9a388f28179e66bebbef350f99CNA
Linux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 531c1aec81bfe19d00af13da5531fbb8209e4bd2531c1aec81bfe19d00af13da5531fbb8209e4bd2CNA
Linux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 719d3932b8f6e3348ce2f0ac58e278301fc17575719d3932b8f6e3348ce2f0ac58e278301fc17575CNA
Linux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < c89477ad79446867394360b29bb801010fc3ff22c89477ad79446867394360b29bb801010fc3ff22CNA
Linux2.6.12–CNA

Scores by source

Linux (CNA)9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: partial

References

refgit.kernel.org/stable/c/47276297140ee6712646f9b19fb04fe26daedd01refgit.kernel.org/stable/c/db76b75ede3810e7cf9cfea5067d4f3e0993768brefgit.kernel.org/stable/c/19e42490c89bac9a388f28179e66bebbef350f99refgit.kernel.org/stable/c/531c1aec81bfe19d00af13da5531fbb8209e4bd2refgit.kernel.org/stable/c/719d3932b8f6e3348ce2f0ac58e278301fc17575refgit.kernel.org/stable/c/c89477ad79446867394360b29bb801010fc3ff22