Medium [CVE-2026-72210] fix off-by-one in mapping pairs decoding bounds checks

In the Linux kernel, the following vulnerability has been resolved: ntfs: fix off-by-one in mapping pairs decoding bounds checks In ntfs_mapping_pairs_decompress(), attr_end points one byte past the end of the attribute record: attr_end = (u8 *)attr + le32_to_cpu(attr->length); The two bounds checks validating that mapping pair data bytes fit within the attribute use strict greater-than (>), which allows a one-byte out-of-bounds read when the data extends exactly to attr_end: b = *buf & 0xf; if (b) { if (unlikely(buf + b > attr_end)) // off-by-one goto io_error; for (deltaxcn = (s8)buf[b--]; b; b--) deltaxcn = (deltaxcn << 8) + buf[b]; } When buf + b == attr_end, the check evaluates to false and buf[b] reads one byte past the valid attribute boundary.

The same pattern appears in the LCN delta bytes check. A flaw was found in the Linux kernel's NTFS filesystem driver.

An error in how the driver checks the boundaries of data it processes, specifically an 'off-by-one' error, allows it to read one byte beyond its intended memory region. This 'out-of-bounds read' could potentially lead to the disclosure of sensitive information from the kernel's memory.

Red Hat severity: Moderate — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-125.