CVE-2026-63964
Description
In the Linux kernel, the following vulnerability has been resolved:
usb: typec: ucsi: ccg: reject firmware images without a ':' record header
do_flash() locates the first .cyacd record with
p = strnchr(fw->data, fw->size, ':');
while (p < eof) {
s = strnchr(p + 1, eof - p - 1, ':');
...
}
If the firmware image contains no ':' byte, strnchr() returns NULL.
NULL compares less than the valid kernel pointer eof, so the loop body
runs and strnchr() is called with p + 1 == (void *)1 and a length of
roughly (unsigned long)eof, causing a wonderful crash.
The not_signed_fw fallthrough earlier in do_flash() and the chip-state
branches in ccg_fw_update_needed() allow an unsigned blob to reach this
loop, so a root user who can place a crafted file under /lib/firmware
and write the do_flash sysfs attribute can trigger the oops.
Bail out with -EINVAL when the initial strnchr() returns NULL.
Metadata
Severity & Metrics
No CVSS data available.
Affected products (2)
| Vendor | Product | Platform | Versions |
|---|---|---|---|
| Linux | Linux | — | 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 < b41dfc033fe594e152648050e95b9489cd53e9e3, 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 < 2f395ca1263bd181995eb829f5943a83a20db213, 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 < 6526f8684f72391138353642af908803ba70795e, 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 < 3f432b8203066c26770fe6ea591361f10021dd6b … |
| Linux | Linux | — | 5.2, 0 < 5.2, 5.10.259 ≤ 5.10.*, 5.15.210 ≤ 5.15.* … |
References (8)
- https://git.kernel.org/stable/c/b41dfc033fe594e152648050e95b9489cd53e9e3
- https://git.kernel.org/stable/c/2f395ca1263bd181995eb829f5943a83a20db213
- https://git.kernel.org/stable/c/6526f8684f72391138353642af908803ba70795e
- https://git.kernel.org/stable/c/3f432b8203066c26770fe6ea591361f10021dd6b
- https://git.kernel.org/stable/c/c4ee519b06389e59ba2d6aa722fcc4a02a8bbcbb
- https://git.kernel.org/stable/c/a38ed87818b2419090fb1a6338ddce6842b65dfa
- https://git.kernel.org/stable/c/c8460de584fe5415d212cfdd127d4db90835a450
- https://git.kernel.org/stable/c/d7486952bf74e546ee3748fb14b2d07881fa6273