CVE-2026-64336

Description

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.

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EPSS — Exploit Prediction

0.0022

Probability of exploitation

0.12%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/2f7a6b8ab3845bd1da02604f1a874b52a4555a72 https://git.kernel.org/stable/c/6bfc8d01ac4068eced509f8fc74d0cd205e4dcec https://git.kernel.org/stable/c/b069b7029862fafaff331d4c664d97d4ae828d6d https://git.kernel.org/stable/c/cf6ca0aefae03958cfb5b189b0adbfb25c06bfac https://git.kernel.org/stable/c/d4b12b6b395e43a2b1d80be3745631fcaa9c047b https://git.kernel.org/stable/c/e1494191a3aac665d3a2fce16169a97c346253ec https://git.kernel.org/stable/c/e52ca411f50539ff1d0c877b9312771ca8a858c1

Frequently Asked Questions

What is CVE-2026-64336? +

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.

How do I check if I'm vulnerable to CVE-2026-64336? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.