CVE-2026-63964: Linux kernel · usb: typec: ucsi: ccg: reject firmware images without a ':' record header
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 30 Oct 2026, 20:25 UTC
Rated Medium by Threat Radar's AI analysis · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- EPSS
- 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation evidence
Disclosed: evidence found.
CVE published 19 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
AI-suggested
Apply the official fix that rejects firmware images lacking a ':' record header by returning -EINVAL early in the firmware update process. Until patched, restrict root user access to /lib/firmware and the do_flash sysfs attribute to prevent exploitation.
Description
A vulnerability in the Linux kernel's USB Type-C UCSI CCG firmware update process allows a crafted firmware image without a ':' record header to cause a kernel crash. This occurs because the code does not properly handle the absence of ':' bytes in the firmware image, leading to a NULL pointer dereference and kernel oops. A root user with the ability to place files under /lib/firmware and write to the do_flash sysfs attribute can trigger this crash. The issue is addressed by rejecting firmware images lacking the required ':' record header.
References
- git.kernel.org/stable/c/b41dfc033fe594e152648050e95b9489cd53e9e3 (opens in a new tab)
- git.kernel.org/stable/c/2f395ca1263bd181995eb829f5943a83a20db213 (opens in a new tab)
- git.kernel.org/stable/c/6526f8684f72391138353642af908803ba70795e (opens in a new tab)
- git.kernel.org/stable/c/3f432b8203066c26770fe6ea591361f10021dd6b (opens in a new tab)
- git.kernel.org/stable/c/c4ee519b06389e59ba2d6aa722fcc4a02a8bbcbb (opens in a new tab)
- git.kernel.org/stable/c/a38ed87818b2419090fb1a6338ddce6842b65dfa (opens in a new tab)
- git.kernel.org/stable/c/c8460de584fe5415d212cfdd127d4db90835a450 (opens in a new tab)
- git.kernel.org/stable/c/d7486952bf74e546ee3748fb14b2d07881fa6273 (opens in a new tab)