net/ncsi: fix heap OOB read in NCSI_CMD_SEND_CMD payload length
Summary
| CVE | CVE-2026-74694 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-22 16:16:43 UTC |
| Updated | 2026-08-22 16:16:43 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: net/ncsi: fix heap OOB read in NCSI_CMD_SEND_CMD payload length ncsi_send_cmd_nl() takes the number of bytes to copy from the attacker-controlled ncsi_pkt_hdr.length field of the in-band packet header, while the source buffer is the NCSI_ATTR_DATA netlink attribute whose readable size is nla_len() - sizeof(ncsi_pkt_hdr). The two length sources are never cross-checked: only nla_len() >= sizeof(struct ncsi_pkt_hdr) is enforced. With hdr->length set larger than the attribute payload (up to 65535 against at most 2032 readable bytes), ncsi_cmd_handler_oem() copies past the end of the netlink attribute buffer with unsafe_memcpy(), leaking up to ~64KB of kernel heap memory into the transmitted NCSI command packet. The destination skb is sized by the declared payload, so the write side does not overflow - this is a pure OOB read / information leak, reachable with CAP_NET_ADMIN on systems with a registered NCSI device (e.g. OpenBMC on Aspeed BMC SoCs, where NET_NCSI=y is standard). Reject commands whose declared payload extends past the end of the data attribute. The issue was found by the autokbug dynamic kernel fuzzer at Tencent Yunding Lab. |
Risk And Classification
EPSS: 0.001770000 probability, percentile 0.071950000 (date 2026-08-24)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 9771b8ccdfa6dcb1ac5128ca7fe8649f3092d392 e60afa01d35f8b2671b27ca93309921427144cce git | Not specified |
| CNA | Linux | Linux | affected 9771b8ccdfa6dcb1ac5128ca7fe8649f3092d392 67c72b8ef63d9d9a610546fda30b116638f39745 git | Not specified |
| CNA | Linux | Linux | affected 9771b8ccdfa6dcb1ac5128ca7fe8649f3092d392 4489b4a17892750131e4bef4bc1d3d703c8fb5ba git | Not specified |
| CNA | Linux | Linux | affected 9771b8ccdfa6dcb1ac5128ca7fe8649f3092d392 43c7d0a6917751ea898ae584d00f24f5deac46d4 git | Not specified |
| CNA | Linux | Linux | affected 9771b8ccdfa6dcb1ac5128ca7fe8649f3092d392 b5231ad0b376b801ab8cf2962b182cc29deaedb3 git | Not specified |
| CNA | Linux | Linux | affected 9771b8ccdfa6dcb1ac5128ca7fe8649f3092d392 02226af69362758046822840fc6a497f5de33f00 git | Not specified |
| CNA | Linux | Linux | affected 9771b8ccdfa6dcb1ac5128ca7fe8649f3092d392 3a60b5af75abe8e3494ccd074fb4ae6e601a3e55 git | Not specified |
| CNA | Linux | Linux | affected 9771b8ccdfa6dcb1ac5128ca7fe8649f3092d392 afa58b7384913c8773d837acdb07b035690ec5d2 git | Not specified |
| CNA | Linux | Linux | affected 4.20 | Not specified |
| CNA | Linux | Linux | unaffected 4.20 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.265 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.216 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.183 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.152 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.104 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.45 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.9 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/67c72b8ef63d9d9a610546fda30b116638f39745 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/3a60b5af75abe8e3494ccd074fb4ae6e601a3e55 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/e60afa01d35f8b2671b27ca93309921427144cce | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/4489b4a17892750131e4bef4bc1d3d703c8fb5ba | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/43c7d0a6917751ea898ae584d00f24f5deac46d4 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/02226af69362758046822840fc6a497f5de33f00 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/b5231ad0b376b801ab8cf2962b182cc29deaedb3 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/afa58b7384913c8773d837acdb07b035690ec5d2 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.