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…
Does this matter?
Lower severity and a low EPSS score (0.17%). Track it; it rarely justifies an emergency change on its own.
Description
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 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.17% probability · 7th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/2214e2bb5489145aba944874d0ee1652a0a63dc8Patch
- https://git.kernel.org/stable/c/53f2cb491b500897a619ff6abd72f565933760f0Patch
- https://git.kernel.org/stable/c/944900fe2736c07288efe2d9394db4d3ca23f2c9Patch
- https://git.kernel.org/stable/c/2214e2bb5489145aba944874d0ee1652a0a63dc8Patch
- https://git.kernel.org/stable/c/53f2cb491b500897a619ff6abd72f565933760f0Patch
- https://git.kernel.org/stable/c/944900fe2736c07288efe2d9394db4d3ca23f2c9Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.