TinyUSB through 0.21.0, fixed in commit e85c2b8, contains an out-of-bounds write vulnerability in the MTP device class helper mtp_container_get_string() in src/class/mtp/mtp.h that allows a malicious USB host to corrupt adjacent memory by supplying a crafted MTP string with an unbounded character count. Attackers can exploit the unchecked memcpy operation copying up to 510 bytes into a fixed-size destination buffer to achieve code execution or cause a denial of service on the TinyUSB MTP device.
https://www.vulncheck.com/advisories/tinyusb-out-of-bounds-write-via-mtp-container-get-string
https://github.com/hathach/tinyusb/commit/e85c2b8affa1efbf00d398d59e7a87d3e61cc4a9
Published: 2026-11-03
Updated: 2026-11-03
Base Score: 7.2
Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C
Severity: High
Base Score: 6.8
Vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Medium
Base Score: 7
Vector: CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00266