CVE-2024-46795
MediumIn the Linux kernel, the following vulnerability has been resolved: ksmbd: unset the binding mark of a reused connection Steve French reported null pointer dereference error from sha256 lib. cifs.ko can send session setup requests on reused connection. If reused connection is used for binding session, conn->binding can still remain true and generate_preauth_hash() will not set sess->Preauth_HashValue and it will be NULL. It is used as a material to create an encryption key in ksmbd_gen_smb311_encryptionkey. ->Preauth_HashValue cause null pointer dereference error from crypto_shash_update(). BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 8 PID: 429254 Comm: kworker/8:39 Hardware name: LENOVO 20MAS08500/20MAS08500, BIOS N2CET69W (1.52 ) Workqueue: ksmbd-io handle_ksmbd_work [ksmbd] RIP: 0010:lib_sha256_base_do_update.isra.0+0x11e/0x1d0 [sha256_ssse3] <TASK> ? show_regs+0x6d/0x80 ? __die+0x24/0x80 ? page_fault_oops+0x99/0x1b0 ? do_user_addr_fault+0x2ee/0x6b0 ? exc_page_fault+0x83/0x1b0 ? asm_exc_page_fault+0x27/0x30 ? __pfx_sha256_transform_rorx+0x10/0x10 [sha256_ssse3] ? lib_sha256_base_do_update.isra.0+0x11e/0x1d0 [sha256_ssse3] ? __pfx_sha256_transform_rorx+0x10/0x10 [sha256_ssse3] ? __pfx_sha256_transform_rorx+0x10/0x10 [sha256_ssse3] _sha256_update+0x77/0xa0 [sha256_ssse3] sha256_avx2_update+0x15/0x30 [sha256_ssse3] crypto_shash_update+0x1e/0x40 hmac_update+0x12/0x20 crypto_shash_update+0x1e/0x40 generate_key+0x234/0x380 [ksmbd] generate_smb3encryptionkey+0x40/0x1c0 [ksmbd] ksmbd_gen_smb311_encryptionkey+0x72/0xa0 [ksmbd] ntlm_authenticate.isra.0+0x423/0x5d0 [ksmbd] smb2_sess_setup+0x952/0xaa0 [ksmbd] __process_request+0xa3/0x1d0 [ksmbd] __handle_ksmbd_work+0x1c4/0x2f0 [ksmbd] handle_ksmbd_work+0x2d/0xa0 [ksmbd] process_one_work+0x16c/0x350 worker_thread+0x306/0x440 ? __pfx_worker_thread+0x10/0x10 kthread+0xef/0x120 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x44/0x70 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK>
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-476CVE-2024-46795 is a NULL Pointer Dereference vulnerability
What is NULL Pointer Dereference?
The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE
Affected versions
Linux kernel versions
5.15
and later are affected. Fixed in
5.15.167,
6.1.110,
6.6.51,
6.10.10,
6.11
and their respective stable series.
References
The following references provide additional information about CVE-2024-46795 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
-
-
PatchKernel patch commithttps://git.kernel.org/stable/c/41bc256da7e47b679df87c7fc7a5b393052b9cce
-
PatchKernel patch commithttps://git.kernel.org/stable/c/4c8496f44f5bb5c06cdef5eb130ab259643392a1
-
PatchKernel patch commithttps://git.kernel.org/stable/c/78c5a6f1f630172b19af4912e755e1da93ef0ab5
Frequently asked questions
-
What is CVE-2024-46795?
CVE-2024-46795 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 5.15 onward and has been patched in 5.15.167, 6.1.110, 6.6.51 and others. CVE-2024-46795 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
-
What is the CVSS score for CVE-2024-46795?
CVE-2024-46795 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2024-46795?
Yes — CVE-2024-46795 has been patched. Fixed versions include 5.15.167, 6.1.110, 6.6.51 and others. If you are running Linux kernel 5.15 or later up to the fix versions, apply the relevant patch for your kernel branch.
-
Is CVE-2024-46795 actively exploited?
No — CVE-2024-46795 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
-
What is NULL Pointer Dereference (CWE-476)?
The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. View CWE-476 on MITRE CWE →