Paper/Archive/CVE-2026-46043

CVE-2026-46043

Linux Linux — RDMA/rxe: Validate pad and ICRC before payload_size() in rxe_rcv

Description · from the CVE record

In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Validate pad and ICRC before payload_size() in rxe_rcv rxe_rcv() currently checks only that the incoming packet is at least header_size(pkt) bytes long before payload_size() is used. However, payload_size() subtracts both the attacker-controlled BTH pad field and RXE_ICRC_SIZE from pkt->paylen: payload_size = pkt->paylen - offset[RXE_PAYLOAD] - bth_pad(pkt) - RXE_ICRC_SIZE This means a short packet can still make payload_size() underflow even if it includes enough bytes for the fixed headers. Simply requiring header_size(pkt) + RXE_ICRC_SIZE is not sufficient either, because a packet with a forged non-zero BTH pad can still leave payload_size() negative and pass an underflowed value to later receive-path users. Fix this by validating pkt->paylen against the full minimum length required by payload_size(): header_size(pkt) + bth_pad(pkt) + RXE_ICRC_SIZE.

Affected

ProductAffectedFixed inSource
Linux8700e3e7c4857d28ebaa824509934556da0b3e76 – < c4376c672c3648d5bdc31dfffc329d07164f93c4c4376c672c3648d5bdc31dfffc329d07164f93c4CNA
Linux8700e3e7c4857d28ebaa824509934556da0b3e76 – < 5fedefec757192dcaad29a664ac332c7601be1445fedefec757192dcaad29a664ac332c7601be144CNA
Linux8700e3e7c4857d28ebaa824509934556da0b3e76 – < 2c0d71ef12f46c57d37bc571f3f2797db7eb50cc2c0d71ef12f46c57d37bc571f3f2797db7eb50ccCNA
Linux8700e3e7c4857d28ebaa824509934556da0b3e76 – < 2fd4f8b749309a61c3f3f88ee8891d94f79e12402fd4f8b749309a61c3f3f88ee8891d94f79e1240CNA
Linux8700e3e7c4857d28ebaa824509934556da0b3e76 – < f83519a4c122c9c7a850a2197648a9ff4c67c520f83519a4c122c9c7a850a2197648a9ff4c67c520CNA
Linux8700e3e7c4857d28ebaa824509934556da0b3e76 – < 9b924f3a26b21330a837cfe72e819b6393bbeeaa9b924f3a26b21330a837cfe72e819b6393bbeeaaCNA
Linux8700e3e7c4857d28ebaa824509934556da0b3e76 – < e8ee0e792d475b1067c199ef0af1b6221fa6f43de8ee0e792d475b1067c199ef0af1b6221fa6f43dCNA
Linux8700e3e7c4857d28ebaa824509934556da0b3e76 – < 7244491dab347f648e661da96dc0febadd9daec37244491dab347f648e661da96dc0febadd9daec3CNA
Linux4.8–CNA

Scores by source

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

References

refgit.kernel.org/stable/c/c4376c672c3648d5bdc31dfffc329d07164f93c4refgit.kernel.org/stable/c/5fedefec757192dcaad29a664ac332c7601be144refgit.kernel.org/stable/c/2c0d71ef12f46c57d37bc571f3f2797db7eb50ccrefgit.kernel.org/stable/c/2fd4f8b749309a61c3f3f88ee8891d94f79e1240refgit.kernel.org/stable/c/f83519a4c122c9c7a850a2197648a9ff4c67c520refgit.kernel.org/stable/c/9b924f3a26b21330a837cfe72e819b6393bbeeaarefgit.kernel.org/stable/c/e8ee0e792d475b1067c199ef0af1b6221fa6f43drefgit.kernel.org/stable/c/7244491dab347f648e661da96dc0febadd9daec3