CVE-2023-52767

In the Linux kernel, the following vulnerability has been resolved: tls: fix NULL deref on tls_sw_splice_eof() with empty record syzkaller discovered that if tls_sw_splice_eof() is executed as part of sendfile() when the plaintext/ciphertext sk_msg are empty, the send path gets confused because the empty ciphertext buffer does not have enough space for the encryption overhead. This causes tls_push_record() to go on the `split = true` path (which is only supposed to be used when interacting with an attached BPF program), and then get further confused and hit the tls_merge_open_record() path, which then assumes that there must be at least one populated buffer element, leading to a NULL deref. It is possible to have empty plaintext/ciphertext buffers if we previously bailed from tls_sw_sendmsg_locked() via the tls_trim_both_msgs() path. tls_sw_push_pending_record() already handles this case correctly; let's do the same check in tls_sw_splice_eof().

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/2214e2bb5489145aba944874d0ee1652a0a63dc8	Patch
https://git.kernel.org/stable/c/53f2cb491b500897a619ff6abd72f565933760f0	Patch
https://git.kernel.org/stable/c/944900fe2736c07288efe2d9394db4d3ca23f2c9	Patch
https://git.kernel.org/stable/c/2214e2bb5489145aba944874d0ee1652a0a63dc8	Patch
https://git.kernel.org/stable/c/53f2cb491b500897a619ff6abd72f565933760f0	Patch
https://git.kernel.org/stable/c/944900fe2736c07288efe2d9394db4d3ca23f2c9	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.7:rc1::::::
	cpe:2.3:o:linux:linux_kernel:6.7:rc2::::::

History

No history.

Information

Published : 2024-05-21 16:15

Updated : 2025-01-06 20:29

NVD link : CVE-2023-52767

Mitre link : CVE-2023-52767

CVE.ORG link : CVE-2023-52767

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-476

NULL Pointer Dereference

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