CVE-2026-63964

usb: typec: ucsi: ccg: reject firmware images without a ':' record header

State
Published
Severity
Not scored
Published
Jul 19, 2026
Updated
Jul 20, 2026
Reserved
Jul 19, 2026

Read the record on cve.org

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.

Scores

The record has no CVSS score.

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
LinuxLinux
  • 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 to before b41dfc033fe594e152648050e95b9489cd53e9e3Affected
  • 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 to before 2f395ca1263bd181995eb829f5943a83a20db213Affected
  • 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 to before 6526f8684f72391138353642af908803ba70795eAffected
  • 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 to before 3f432b8203066c26770fe6ea591361f10021dd6bAffected
  • 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 to before c4ee519b06389e59ba2d6aa722fcc4a02a8bbcbbAffected
  • 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 to before a38ed87818b2419090fb1a6338ddce6842b65dfaAffected
  • 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 to before c8460de584fe5415d212cfdd127d4db90835a450Affected
  • 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401 to before d7486952bf74e546ee3748fb14b2d07881fa6273Affected
LinuxLinux
  • 5.2Affected
  • before 5.2Not affected
  • 5.10.259 through 5.10.*Not affected
  • 5.15.210 through 5.15.*Not affected
  • 6.1.176 through 6.1.*Not affected
  • 6.6.143 through 6.6.*Not affected
  • 6.12.93 through 6.12.*Not affected
  • 6.18.35 through 6.18.*Not affected
  • 7.0.12 through 7.0.*Not affected
  • 7.1 and laterNot affected

References

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