CVE-2026-46114
Vulnerability Summary
Timeline
Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Reject non-8-byte ATOMIC_WRITE payloads atomic_write_reply() at drivers/infiniband/sw/rxe/rxe_resp.c unconditionally dereferences 8 bytes at payload_addr(pkt): value = *(u64 *)payload_addr(pkt); check_rkey() previously accepted an ATOMIC_WRITE request with pktlen == resid == 0 because the length validation only compared pktlen against resid. A remote initiator that sets the RETH length to 0 therefore reaches atomic_write_reply() with a zero-byte logical payload, and the responder reads sizeof(u64) bytes from past the logical end of the packet into skb->head tailroom, then writes those 8 bytes into the attacker's MR via rxe_mr_do_atomic_write(). That is a remote disclosure of 4 bytes of kernel tailroom per probe (the other 4 bytes are the packet's own trailing ICRC). IBA oA19-28 defines ATOMIC_WRITE as exactly 8 bytes. Anything else is protocol-invalid. Hoist a strict length check into check_rkey() so the responder never reaches the unchecked dereference, and keep the existing WRITE-family length logic for the normal RDMA WRITE path. Reproduced on mainline with an unmodified rxe driver: a sustained zero-length ATOMIC_WRITE probe repeatedly leaks adjacent skb head-buffer bytes into the attacker's MR, including recognisable kernel strings and partial kernel-direct-map pointer words. With this patch applied the responder rejects the PDU and the MR stays all-zero.
CVSS Metrics
- v3.1•HIGH•Score: 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Trends
Current EPSS score: 0.47%• Percentile: 40%
Techniques & Countermeasures
- CWE-476•NULL Pointer Dereference
The product dereferences a pointer that it expects to be valid but is NULL.
Affected Systems
- debian•linux
< 6.12.88-1 | < 7.0.7-1
- ubuntu•linux
< 6.8.0-136.136 | all | < 7.0.0-28.28
- ubuntu•linux-allwinner-5.19
all
- ubuntu•linux-aws
< 6.8.0-1061.64 | all | < 7.0.0-1009.9
- ubuntu•linux-aws-5.0
all
- ubuntu•linux-aws-5.11
all
- ubuntu•linux-aws-5.13
all
- ubuntu•linux-aws-5.19
all
- ubuntu•linux-aws-5.3
all
- ubuntu•linux-aws-5.8
all
- ubuntu•linux-aws-6.14
all
- ubuntu•linux-aws-6.17
all
- ubuntu•linux-aws-6.2
all
- ubuntu•linux-aws-6.5
all
- ubuntu•linux-aws-6.8
< 6.8.0-1061.64~22.04.1
- ubuntu•linux-aws-fips
< 6.8.0-1061.64+fips1
- ubuntu•linux-azure
all | < 6.8.0-1063.71 | all | < 7.0.0-1010.10
- ubuntu•linux-azure-5.11
all
- ubuntu•linux-azure-5.13
all
- ubuntu•linux-azure-5.19
all
- ubuntu•linux-azure-5.3
all
- ubuntu•linux-azure-5.8
all
- ubuntu•linux-azure-6.11
all
- ubuntu•linux-azure-6.14
all
- ubuntu•linux-azure-6.17
all
- ubuntu•linux-azure-6.2
all
- ubuntu•linux-azure-6.5
all
- ubuntu•linux-azure-6.8
< 6.8.0-1063.71~22.04.1
- ubuntu•linux-azure-7.0
all
- ubuntu•linux-azure-edge
all
- ubuntu•linux-azure-fde
all | < 6.8.0-1062.69 | all | < 7.0.0-1009.9
- ubuntu•linux-azure-fde-5.19
all
- ubuntu•linux-azure-fde-6.14
all
- ubuntu•linux-azure-fde-6.2
all
- ubuntu•linux-azure-fde-6.8
< 6.8.0-1062.69~22.04.1
- ubuntu•linux-azure-fips
< 6.8.0-1063.71+fips2
- ubuntu•linux-azure-nvidia
all
- ubuntu•linux-azure-nvidia-6.14
all
- ubuntu•linux-bluefield
all | < 6.8.0-1028.33
- ubuntu•linux-fips
< 6.8.0-136.136+fips2
- ubuntu•linux-gcp
all | < 6.8.0-1064.72 | all | < 7.0.0-1008.8
- ubuntu•linux-gcp-5.11
all
- ubuntu•linux-gcp-5.13
all
- ubuntu•linux-gcp-5.19
all
- ubuntu•linux-gcp-5.3
all
- ubuntu•linux-gcp-5.8
all
- ubuntu•linux-gcp-6.11
all
- ubuntu•linux-gcp-6.14
all
- ubuntu•linux-gcp-6.17
all
- ubuntu•linux-gcp-6.2
all
Showing first 50 affected entries in server-rendered view.
References (32)
- https://git.kernel.org/stable/c/539cabb7b2d8ba70f55bba91db55faef11c2a6d7
- https://git.kernel.org/stable/c/d415fce3fcde6d7aeea6c25362a395b905811452
- https://git.kernel.org/stable/c/105bf79a23b85cf3a761d18a4f3e10ce88526bc1
- https://git.kernel.org/stable/c/7ec1ed4747f5f99f8b797bb438c5efd36079fad5
- https://git.kernel.org/stable/c/1114c87aa6f195cf07da55a27b2122ae26557b26
- https://ubuntu.com/security/CVE-2026-46114
- https://www.cve.org/CVERecord?id=CVE-2026-46114
- https://git.kernel.org/linus/1114c87aa6f195cf07da55a27b2122ae26557b26
- https://ubuntu.com/security/notices/USN-8566-1
- https://ubuntu.com/security/notices/USN-8568-1
- https://ubuntu.com/security/notices/USN-8569-1
- https://ubuntu.com/security/notices/USN-8567-1
- https://ubuntu.com/security/notices/USN-8574-1
- https://ubuntu.com/security/notices/USN-8593-1
- https://ubuntu.com/security/notices/USN-8574-2
- https://ubuntu.com/security/notices/USN-8595-1
- https://ubuntu.com/security/notices/USN-8596-1
- https://ubuntu.com/security/notices/USN-8603-1
- https://ubuntu.com/security/notices/USN-8595-2
- https://ubuntu.com/security/notices/USN-8606-1
- https://ubuntu.com/security/notices/USN-8607-1
- https://ubuntu.com/security/notices/USN-8608-1
- https://ubuntu.com/security/notices/USN-8609-1
- https://ubuntu.com/security/notices/USN-8618-1
- https://ubuntu.com/security/notices/USN-8574-3
- https://ubuntu.com/security/notices/USN-8595-3
- https://ubuntu.com/security/notices/USN-8619-1
- https://security-tracker.debian.org/tracker/CVE-2026-46114
- https://ubuntu.com/security/notices/USN-8663-1
- https://ubuntu.com/security/notices/USN-8664-1
- https://ubuntu.com/security/notices/USN-8665-1
- https://ubuntu.com/security/notices/USN-8728-1