CVE-2026-63964
Last modified
CVE-2026-63964 is a vulnerability of currently unknown severity. 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.. EPSS estimates a 0.21% chance of exploitation in the next 30 days.
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.
Metrics
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401, < b41dfc033fe594e152648050e95b9489cd53e9e3; >= 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401, < 2f395ca1263bd181995eb829f5943a83a20db213; >= 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401, < 6526f8684f72391138353642af908803ba70795e; >= 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401, < 3f432b8203066c26770fe6ea591361f10021dd6b; >= 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401, < c4ee519b06389e59ba2d6aa722fcc4a02a8bbcbb; >= 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401, < a38ed87818b2419090fb1a6338ddce6842b65dfa; >= 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401, < c8460de584fe5415d212cfdd127d4db90835a450; >= 5c9ae5a87573d38cfc4c740aafda2fa6ce06e401, < d7486952bf74e546ee3748fb14b2d07881fa6273 |
| Linux | Linux | 5.2 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
Frequently Asked Questions
What is CVE-2026-63964?
How severe is CVE-2026-63964?
How do I fix CVE-2026-63964?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-63959In the Linux kernel, the following vulnerability has been re…
- CVE-2026-6396The Fast & Fancy Filter – 3F plugin for WordPress is vulnera…4.3
- CVE-2026-63960In the Linux kernel, the following vulnerability has been re…
- CVE-2026-63961In the Linux kernel, the following vulnerability has been re…
- CVE-2026-63962In the Linux kernel, the following vulnerability has been re…
- CVE-2026-63963In the Linux kernel, the following vulnerability has been re…
- CVE-2026-63965In the Linux kernel, the following vulnerability has been re…
- CVE-2026-63966In the Linux kernel, the following vulnerability has been re…
- CVE-2026-63967In the Linux kernel, the following vulnerability has been re…
- CVE-2026-63968In the Linux kernel, the following vulnerability has been re…7.5
- CVE-2026-63969In the Linux kernel, the following vulnerability has been re…
- CVE-2026-6397The Sticky plugin for WordPress is vulnerable to Stored Cros…6.4
Are you affected by CVE-2026-63964?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST
