In the Linux kernel, the following vulnerability has been resolved:
can: gw: fix OOB heap access in cgw_csum_crc8_rel()
cgw_csum_crc8_rel() correctly computes bounds-safe indices via calc_idx():
int from = calc_idx(crc8->from_idx, cf->len);
int to = calc_idx(crc8->to_idx, cf->len);
int res = calc_idx(crc8->result_idx, cf->len);
if (from < 0 || to < 0 || res < 0)
return;
However, the loop and the result write then use the raw s8 fields directly
instead of the computed variables:
for (i = crc8->from_idx; ...) /* BUG: raw negative index */
cf->data[crc8->result_idx] = ...; /* BUG: raw negative index */
With from_idx = to_idx = result_idx = -64 on a 64-byte CAN FD frame,
calc_idx(-64, 64) = 0 so the guard passes, but the loop iterates with
i = -64, reading cf->data[-64], and the write goes to cf->data[-64].
This write might end up to 56 (7.0-rc) or 40 (<= 6.19) bytes before the
start of the canfd_frame on the heap.
The companion function cgw_csum_xor_rel() uses `from`/`to`/`res`
correctly throughout; fix cgw_csum_crc8_rel() to match.
Confirmed with KASAN on linux-7.0-rc2:
BUG: KASAN: slab-out-of-bounds in cgw_csum_crc8_rel+0x515/0x5b0
Read of size 1 at addr ffff8880076619c8 by task poc_cgw_oob/62
To configure the can-gw crc8 checksums CAP_NET_ADMIN is needed.
References
Configurations
Configuration 1 (hide)
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History
27 Apr 2026, 20:33
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://git.kernel.org/stable/c/54ecdf76a55e75c1f5085e440f8ab671a3283ef5 - Patch | |
| References | () https://git.kernel.org/stable/c/66b689efd08227da2c5ca49b58b30a95d23c695a - Patch | |
| References | () https://git.kernel.org/stable/c/84f8b76d24273175a22713e83e90874e1880d801 - Patch | |
| References | () https://git.kernel.org/stable/c/999ca48d55a8a46da21519db7e834e5867200379 - Patch | |
| References | () https://git.kernel.org/stable/c/a025283d7f7404c739225e457fb99db2368bb544 - Patch | |
| References | () https://git.kernel.org/stable/c/b9c310d72783cc2f30d103eed83920a5a29c671a - Patch | |
| References | () https://git.kernel.org/stable/c/c4e8eaa75fa0b6bcbfa5356d6195c4ad0e05e57a - Patch | |
| References | () https://git.kernel.org/stable/c/e7c99348b0612b2bc02d5ce6ff9873261cc7605f - Patch | |
| First Time |
Linux
Linux linux Kernel |
|
| CPE | cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.4:-:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:* |
|
| CWE | CWE-125 |
27 Apr 2026, 15:16
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 8.8 |
24 Apr 2026, 15:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-04-24 15:16
Updated : 2026-06-17 10:33
NVD link : CVE-2026-31570
Mitre link : CVE-2026-31570
CVE.ORG link : CVE-2026-31570
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-125
Out-of-bounds Read