In the Linux kernel, the following vulnerability has been resolved: USB: serial: keyspan_pda: fix information leak The write() callback is supposed to return the number of characters accepted or a negative errno. Since the addition of write fifo support the keyspan_pda implementation will however return the number characters submitted to the device if the write urb is not already in use. If this number is larger than the number of characters passed to write(), the line discipline continues writing data from beyond the tty write buffer. Fix the information leak by making sure that keyspan_pda_write_start() returns zero on success as intended.

A flaw was found in the Linux kernel's keyspan_pda USB serial driver. An issue with the write() callback function allows it to report more data written than was actually provided. This can lead to the system writing data beyond its allocated buffer, resulting in an information leak. A local attacker could exploit this to potentially gain access to sensitive information.

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Out of support scope kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Fix deferred kernel Red Hat Enterprise Linux 8 Fix deferred kernel-rt Red Hat Enterprise Linux 9 Fix deferred kernel Red Hat Enterprise Linux 9 Fix deferred kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-64336 https://nvd.nist.gov/vuln/detail/CVE-2026-64336 https://lore.kernel.org/linux-cve-announce/2026072515-CVE-2026-64336-82b2@gregkh/T