usb: typec: ucsi: Handle incorrect num_connectors capability

Summary

In the Linux kernel, the following vulnerability has been resolved: usb: typec: ucsi: Handle incorrect num_connectors capability The UCSI spec states that the num_connectors field is 7 bits, and the 8th bit is reserved and should be set to zero. Some buggy FW has been known to set this bit, and it can lead to a system not booting. Flag that the FW is not behaving correctly, and auto-fix the value so that the system boots correctly. Found on Lenovo P1 G8 during Linux enablement program. The FW will be fixed, but seemed worth addressing in case it hit platforms that aren't officially Linux supported.

Timeline

1. Jan 14, 2026, 3:05 PM UTCCVE published
2. Jun 10, 2026, 8:41 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Oct 19, 2026, 6:15 PM UTCRecord last updated

Affected versions

• Linux Linux

  From c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f · fixed in 07c8d2a109d847775b3b4e2c3294c8e1eea75432; From c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f · fixed in 58941bbb0050e365a98c64f1fc4a9a0ac127dba6; From c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f · fixed in f72f97d0aee4a993a35f2496bca5efd24827235d; From c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f · fixed in 914605b0de8128434eafc9582445306830748b93; From c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f · fixed in 3042a57a8e8bce4a3100c3f6f03dc372aab24943; From c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f · fixed in 132fe187e0d940f388f839fe2cde9b84106ad20d; From c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f · fixed in 30cd2cb1abf4c4acdb1ddb468c946f68939819fb

• Linux Linux

  4.13

• KernelLinux

  From 4.13.0 · fixed in 5.10.248; From 5.11.0 · fixed in 5.15.198; From 5.16.0 · fixed in 6.1.160; From 6.2.0 · fixed in 6.6.120; From 6.7.0 · fixed in 6.12.64; From 6.13.0 · fixed in 6.18.3

References 7