| Name | CVE-2025-21704 |
| Description | In the Linux kernel, the following vulnerability has been resolved: usb: cdc-acm: Check control transfer buffer size before access If the first fragment is shorter than struct usb_cdc_notification, we can't calculate an expected_size. Log an error and discard the notification instead of reading lengths from memory outside the received data, which can lead to memory corruption when the expected_size decreases between fragments, causing `expected_size - acm->nb_index` to wrap. This issue has been present since the beginning of git history; however, it only leads to memory corruption since commit ea2583529cd1 ("cdc-acm: reassemble fragmented notifications"). A mitigating factor is that acm_ctrl_irq() can only execute after userspace has opened /dev/ttyACM*; but if ModemManager is running, ModemManager will do that automatically depending on the USB device's vendor/product IDs and its other interfaces. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-4102-1, DLA-4178-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| linux (PTS) | bullseye | 5.10.223-1 | vulnerable |
| bullseye (security) | 5.10.237-1 | fixed | |
| bookworm | 6.1.137-1 | fixed | |
| bookworm (security) | 6.1.140-1 | fixed | |
| trixie | 6.12.27-1 | fixed | |
| sid | 6.12.29-1 | fixed | |
| linux-6.1 (PTS) | bullseye (security) | 6.1.137-1~deb11u1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| linux | source | bullseye | 5.10.237-1 | DLA-4178-1 | ||
| linux | source | bookworm | 6.1.129-1 | |||
| linux | source | (unstable) | 6.12.16-1 | |||
| linux-6.1 | source | bullseye | 6.1.129-1~deb11u1 | DLA-4102-1 |
https://git.kernel.org/linus/e563b01208f4d1f609bcab13333b6c0e24ce6a01 (6.14-rc3)
https://project-zero.issues.chromium.org/issues/395107243