CVE-2024-26995: linux Off-by-one Error

Vulnerability summary

CVE-2024-26995 is a high (CVSS 7.8) Off-by-one Error vulnerability in linux. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 13.9% of scored vulnerabilities.

Timeline

1. 01-05-2024
   PublishedVulnerability first disclosed.
2. 11-05-2026
   Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: usb: typec: tcpm: Correct the PDO counting in pd_set Off-by-one errors happen because nr_snk_pdo and nr_src_pdo are incorrectly added one. The index of the loop is equal to the number of PDOs to be updated when leaving the loop and it doesn't need to be added one. When doing the power negotiation, TCPM relies on the "nr_snk_pdo" as the size of the local sink PDO array to match the Source capabilities of the partner port. If the off-by-one overflow occurs, a wrong RDO might be sent and unexpected power transfer might happen such as over voltage or over current (than expected). "nr_src_pdo" is used to set the Rp level when the port is in Source role. It is also the array size of the local Source capabilities when filling up the buffer which will be sent as the Source PDOs (such as in Power Negotiation). If the off-by-one overflow occurs, a wrong Rp level might be set and wrong Source PDOs will be sent to the partner port. This could potentially cause over current or port resets.

• CWE-193Off-by-one ErrorA product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.