CVE - CVE-2025-21704

CVE-ID
CVE-2025-21704	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
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.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
MISC:https://git.kernel.org/stable/c/383d516a0ebc8641372b521c8cb717f0f1834831 URL:https://git.kernel.org/stable/c/383d516a0ebc8641372b521c8cb717f0f1834831 MISC:https://git.kernel.org/stable/c/6abb510251e75f875797d8983a830e6731fa281c URL:https://git.kernel.org/stable/c/6abb510251e75f875797d8983a830e6731fa281c MISC:https://git.kernel.org/stable/c/7828e9363ac4d23b02419bf2a45b9f1d9fb35646 URL:https://git.kernel.org/stable/c/7828e9363ac4d23b02419bf2a45b9f1d9fb35646 MISC:https://git.kernel.org/stable/c/e563b01208f4d1f609bcab13333b6c0e24ce6a01 URL:https://git.kernel.org/stable/c/e563b01208f4d1f609bcab13333b6c0e24ce6a01 MISC:https://git.kernel.org/stable/c/f64079bef6a8a7823358c3f352ea29a617844636 URL:https://git.kernel.org/stable/c/f64079bef6a8a7823358c3f352ea29a617844636
Assigning CNA
kernel.org
Date Record Created
20241229	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20241229)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
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