VulnerabilityModified

CVE-2024-49996

In the Linux kernel, the following vulnerability has been resolved: cifs: Fix buffer overflow when parsing NFS reparse points ReparseDataLength is sum of the InodeType size and DataBuffer size.

HIGH 7.8EPSS 0.79%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.79%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

In the Linux kernel, the following vulnerability has been resolved: cifs: Fix buffer overflow when parsing NFS reparse points ReparseDataLength is sum of the InodeType size and DataBuffer size. So to get DataBuffer size it is needed to subtract InodeType's size from ReparseDataLength. Function cifs_strndup_from_utf16() is currentlly accessing buf->DataBuffer at position after the end of the buffer because it does not subtract InodeType size from the length. Fix this problem and correctly subtract variable len. Member InodeType is present only when reparse buffer is large enough. Check for ReparseDataLength before accessing InodeType to prevent another invalid memory access. Major and minor rdev values are present also only when reparse buffer is large enough. Check for reparse buffer size before calling reparse_mkdev().

CVSS 3.1: 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.79% probability · 54th percentile
CISA KEV: Not listed
Weakness: CWE-120
Affected: debian/debian linux · linux/linux kernel
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.