CVE-2026-46114RDMA/rxe: Reject non-8-byte ATOMIC_WRITE payloads
Updated under an hour ago ()
Does this affect you?
It affects Linux and 1 other product. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
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
- 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- 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
- Undergoing Analysis
- Record last updated
- Oct 16, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Linux Linux linux:linux (from the name) | from 034e285f8b99062a0cf29112e1232154a6a44aa5 before 539cabb7b2d8ba70f55bba91db55faef11c2a6d7; from 034e285f8b99062a0cf29112e1232154a6a44aa5 before d415fce3fcde6d7aeea6c25362a395b905811452; from 034e285f8b99062a0cf29112e1232154a6a44aa5 before 105bf79a23b85cf3a761d18a4f3e10ce88526bc1; 034e285f8b99062a0cf29112e1232154a6a44aa5 builds before 7ec1ed4747f5f99f8b797bb438c5efd36079fad5; from 034e285f8b99062a0cf29112e1232154a6a44aa5 before 1114c87aa6f195cf07da55a27b2122ae26557b26 | CNA record |
linux linux_kernel linux:linux_kernel | from 6.2 before 6.6.140; from 6.7 before 6.12.88; from 6.13 before 6.18.30; from 6.19 before 7.0.7; 7.1; 7.1 | NVD |
References
- https://git.kernel.org/stable/c/539cabb7b2d8ba70f55bba91db55faef11c2a6d7patch
- https://git.kernel.org/stable/c/d415fce3fcde6d7aeea6c25362a395b905811452patch
- https://git.kernel.org/stable/c/105bf79a23b85cf3a761d18a4f3e10ce88526bc1patch
- https://git.kernel.org/stable/c/7ec1ed4747f5f99f8b797bb438c5efd36079fad5patch
- https://git.kernel.org/stable/c/1114c87aa6f195cf07da55a27b2122ae26557b26patch
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.