CVE-2026-89726
Low risk· EPSS 6%Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
In the Linux kernel, ucs2_strnlen() in lib/ucs2_string.c checks the current character before checking whether the caller-provided maximum length has been reached. If the input is not NUL-terminated within that bound, the loop can read one ucs2_char_t past the limit, causing an off-by-one out-of-bounds read.
Risk Assessment
An out-of-bounds read can lead to kernel memory disclosure or a system crash (oops/panic), posing a risk to system stability and confidentiality.
Recommendation
Update the Linux kernel to a version containing the fix that tests the length before dereferencing the character in ucs2_strnlen().
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Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: lib/ucs2_string.c: fix out-of-bounds read in ucs2_strnlen() Patch series "lib/ucs2_string.c: fix out-of-bounds read in ucs2_strnlen()", v2. This series fixes an off-by-one out-of-bounds read in ucs2_strnlen(). The first patch is the real fix, the second patch comes as a bonus and fixes the code indentation. This patch (of 2): ucs2_strnlen() checks the current character before checking whether the caller-provided maximum length has been reached. If the input is not NUL-terminated within that bound, the loop can read one ucs2_char_t past the limit. Test the length before dereferencing to prevent an off-by-one out-of-bounds read.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

