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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

CVE ID
CVE-2026-63964
State
PUBLISHED
Assigner
Linux
Reserved
2026-07-19 07:54 UTC
Published
2026-07-19 14:55 UTC
Last updated
2026-07-20 06:41 UTC
Vendor / Product
Linux / Linux
Sources
cve.org  ·  NVD

Severity & Metrics

No CVSS data available.

Affected products (2)
VendorProductPlatformVersions
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.* …
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