CVE-2026-45935

Description

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Fix slab-out-of-bounds read in DeleteIndexEntryRoot In the 'DeleteIndexEntryRoot' case of the 'do_action' function, the entry size ('esize') is retrieved from the log record without adequate bounds checking. Specifically, the code calculates the end of the entry ('e2') using: e2 = Add2Ptr(e1, esize); It then calculates the size for memmove using 'PtrOffset(e2, ...)', which subtracts the end pointer from the buffer limit. If 'esize' is maliciously large, 'e2' exceeds the used buffer size. This results in a negative offset which, when cast to size_t for memmove, interprets as a massive unsigned integer, leading to a heap buffer overflow. This commit adds a check to ensure that the entry size ('esize') strictly fits within the remaining used space of the index header before performing memory operations.

CVSS v3.1 Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0016

Probability of exploitation

0.06%

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/36c03f7f177b34d51f1cf1d2304b1074607bf4b0 https://git.kernel.org/stable/c/78942172d5bff4d4afed8674abc09cc560ce44a0 https://git.kernel.org/stable/c/a584b9d1059b29e97e17c919274e9adfb846f2a0 https://git.kernel.org/stable/c/b271c9cb85927210b1b799e55ee7f702d12b4336 https://git.kernel.org/stable/c/b2bc7c44ed1779fc9eaab9a186db0f0d01439622 https://git.kernel.org/stable/c/c065541b71b79874c83d418a9acd18ad5826339b https://git.kernel.org/stable/c/f3b437a4c3e022a1449658ae9f3dd34859894513

Frequently Asked Questions

What is CVE-2026-45935? +

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Fix slab-out-of-bounds read in DeleteIndexEntryRoot In the 'DeleteIndexEntryRoot' case of the 'do_action' function, the entry size ('esize') is retrieved from the log record without adequate bounds checking. Specifically, the code calculates the end of the entry ('e2') using: e2 = Add2Ptr(e1, esize); It then calculates the size for memmove using 'PtrOffset(e2, ...)', which subtracts the end pointer from the buffer limit. If 'esize' is maliciously large, 'e2' exceeds the used buffer size. This results in a negative offset which, when cast to size_t for memmove, interprets as a massive unsigned integer, leading to a heap buffer overflow. This commit adds a check to ensure that the entry size ('esize') strictly fits within the remaining used space of the index header before performing memory operations. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2026-45935? +

CVE-2026-45935 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0016, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-45935? +

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.