CVE-2023-3347

A vulnerability was found in Samba's SMB2 packet signing mechanism. The SMB2 packet signing is not enforced if an admin configured "server signing = required" or for SMB2 connections to Domain Controllers where SMB2 packet signing is mandatory. This flaw allows an attacker to perform attacks, such as a man-in-the-middle attack, by intercepting the network traffic and modifying the SMB2 messages between client and server, affecting the integrity of the data.

Samba is a suite of programs for Linux and Unix to interoperate with Windows.

Security Fix(es):

An out-of-bounds read vulnerability was found in Samba due to insufficient length checks in winbindd_pam_auth_crap.c. When performing NTLM authentication, the client replies to cryptographic challenges back to the server. These replies have variable lengths, and Winbind fails to check the lan manager response length. When Winbind is used for NTLM authentication, a maliciously crafted request can trigger an out-of-bounds read in Winbind, possibly resulting in a crash.(CVE-2022-2127)

A vulnerability was found in Samba's SMB2 packet signing mechanism. The SMB2 packet signing is not enforced if an admin configured "server signing = required" or for SMB2 connections to Domain Controllers where SMB2 packet signing is mandatory. This flaw allows an attacker to perform attacks, such as a man-in-the-middle attack, by intercepting the network traffic and modifying the SMB2 messages between client and server, affecting the integrity of the data.(CVE-2023-3347)

An infinite loop vulnerability was found in Samba's mdssvc RPC service for Spotlight. When parsing Spotlight mdssvc RPC packets sent by the client, the core unmarshalling function sl_unpack_loop() did not validate a field in the network packet that contains the count of elements in an array-like structure. By passing 0 as the count value, the attacked function will run in an endless loop consuming 100% CPU. This flaw allows an attacker to issue a malformed RPC request, triggering an infinite loop, resulting in a denial of service condition.(CVE-2023-34966)

A Type Confusion vulnerability was found in Samba's mdssvc RPC service for Spotlight. When parsing Spotlight mdssvc RPC packets, one encoded data structure is a key-value style dictionary where the keys are character strings, and the values can be any of the supported types in the mdssvc protocol. Due to a lack of type checking in callers of the dalloc_value_for_key() function, which returns the object associated with a key, a caller may trigger a crash in talloc_get_size() when talloc detects that the passed-in pointer is not a valid talloc pointer. With an RPC worker process shared among multiple client connections, a malicious client or attacker can trigger a process crash in a shared RPC mdssvc worker process, affecting all other clients this worker serves.(CVE-2023-34967)

Samba is a suite of programs for Linux and Unix to interoperate with Windows.

Security Fix(es):

An out-of-bounds read vulnerability was found in Samba due to insufficient length checks in winbindd_pam_auth_crap.c. When performing NTLM authentication, the client replies to cryptographic challenges back to the server. These replies have variable lengths, and Winbind fails to check the lan manager response length. When Winbind is used for NTLM authentication, a maliciously crafted request can trigger an out-of-bounds read in Winbind, possibly resulting in a crash.(CVE-2022-2127)

A vulnerability was found in Samba's SMB2 packet signing mechanism. The SMB2 packet signing is not enforced if an admin configured "server signing = required" or for SMB2 connections to Domain Controllers where SMB2 packet signing is mandatory. This flaw allows an attacker to perform attacks, such as a man-in-the-middle attack, by intercepting the network traffic and modifying the SMB2 messages between client and server, affecting the integrity of the data.(CVE-2023-3347)

An infinite loop vulnerability was found in Samba's mdssvc RPC service for Spotlight. When parsing Spotlight mdssvc RPC packets sent by the client, the core unmarshalling function sl_unpack_loop() did not validate a field in the network packet that contains the count of elements in an array-like structure. By passing 0 as the count value, the attacked function will run in an endless loop consuming 100% CPU. This flaw allows an attacker to issue a malformed RPC request, triggering an infinite loop, resulting in a denial of service condition.(CVE-2023-34966)

A Type Confusion vulnerability was found in Samba's mdssvc RPC service for Spotlight. When parsing Spotlight mdssvc RPC packets, one encoded data structure is a key-value style dictionary where the keys are character strings, and the values can be any of the supported types in the mdssvc protocol. Due to a lack of type checking in callers of the dalloc_value_for_key() function, which returns the object associated with a key, a caller may trigger a crash in talloc_get_size() when talloc detects that the passed-in pointer is not a valid talloc pointer. With an RPC worker process shared among multiple client connections, a malicious client or attacker can trigger a process crash in a shared RPC mdssvc worker process, affecting all other clients this worker serves.(CVE-2023-34967)

A vulnerability was found in Samba's SMB2 packet signing mechanism. The SMB2 packet signing is not enforced if an admin configured "server signing = required" or for SMB2 connections to Domain Controllers where SMB2 packet signing is mandatory. This flaw allows an attacker to perform attacks, such as a man-in-the-middle attack, by intercepting the network traffic and modifying the SMB2 messages between client and server, affecting the integrity of the data.

Samba is an open-source implementation of the Server Message Block (SMB) protocol and the related Common Internet File System (CIFS) protocol, which allow PC-compatible machines to share files, printers, and various information.

Security Fix(es):

• samba: SMB2 packet signing is not enforced when "server signing = required" is set (CVE-2023-3347)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• The trust relationship between this workstation and the primary domain failed (BZ#2223600)

Samba is an open-source implementation of the Server Message Block (SMB) protocol and the related Common Internet File System (CIFS) protocol, which allow PC-compatible machines to share files, printers, and various information.

Security Fix(es):

• samba: SMB2 packet signing is not enforced when "server signing = required" is set (CVE-2023-3347)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• The trust relationship between this workstation and the primary domain failed (BZ#2223601)

Out-of-bounds read due to insufficient length checks in winbindd_pam_auth_crap.c (CVE-2022-2127) Improper SMB2 packet signing mechanism leading to man in the middle risk (CVE-2023-3347) Infinite loop vulnerability was found in Samba's mdssvc RPC service for Spotlight (CVE-2023-34966) Type Confusion vulnerability was found in Samba's mdssvc RPC service for Spotlight (CVE-2023-34967) Path disclosure vulnerability in the Spotlight protocol (CVE-2023-34968)

These are all security issues fixed in the ctdb-4.18.5+git.313.c8e274c7852-1.1 package on the GA media of openSUSE Tumbleweed.

This update for samba fixes the following issues:

samba was updated to version 4.17.9:

• CVE-2022-2127: Fixed issue where lm_resp_len was not checked properly in winbindd_pam_auth_crap_send (bsc#1213174).
• CVE-2023-34966: Fixed samba spotlight mdssvc RPC Request Infinite Loop Denial-of-Service Vulnerability (bsc#1213173).
• CVE-2023-34967: Fixed samba spotlight mdssvc RPC Request Type Confusion Denial-of-Service Vulnerability (bsc#1213172).
• CVE-2023-34968: Fixed spotlight server-side Share Path Disclosure (bsc#1213171).
• CVE-2023-3347: Fixed issue where SMB2 packet signing not enforced (bsc#1213170).
• CVE-2020-25720: Fixed issue where creating child permission allowed full write to all attributes (bsc#1213386).

Bugfixes:

• Fixed trust relationship failure (bsc#1213384).
• Backported --pidl-developer fixes.
• Fixed smbd_scavenger crash when service smbd is stopped.
• Fixed issue where vfs_fruit might cause a failing open for delete.
• Fixed named crashes on DLZ zone update.
• Fixed issue where winbind recurses into itself via rpcd_lsad.
• Fixed cli_list looping 100% CPU against pre-lanman2 servers.
• Fixed smbclient leaks fds with showacls.
• Fixed aes256 smb3 encryption algorithms not allowed in smb3_sid_parse().
• Fixed winbindd getting stuck on NT_STATUS_RPC_SEC_PKG_ERROR.
• Fixed smbget memory leak if failed to download files recursively.
• Fixed log flood: smbd_calculate_access_mask_fsp: Access denied: message level should be lower.
• Fixed floating point exception (FPE) via cli_pull_send at source3/libsmb/clireadwrite.c.
• Fixed test_tstream_more_tcp_user_timeout_spin fails intermittently on Rackspace GitLab runners.
• Reduce flapping of ridalloc test.
• Fixed unreliable large_ldap test.
• Fixed filename parser not checking veto files smb.conf parameter.
• Fixed mdssvc may crash when initializing.
• Fixed broken large directory optimization for non-lcomp path elements
• Fixed streams_depot failing to create streams.
• Fixed shadow_copy2 and streams_depot issues.
• Fixed wbinfo -u fails on ad dc with >1000 users.
• Fixed winbindd idmap child contacting the domain controller without a need.
• Fixed idmap_autorid may fail to map sids of trusted domains for the first time.
• Fixed idmap_hash doesn't use ID_TYPE_BOTH for reverse mappings.
• Fixed net ads search -P doesn't work against servers in other domains.
• Fixed DS ACEs might be inherited to unrelated object classes.
• Fixed temporary smbXsrv_tcon_global.tdb can't be parsed.
• Fixed setting veto files = /.*/ breaking listing directories (bsc#1212375).
• Fixed dsgetdcname assuming local system uses IPv4.

It was discovered that Samba incorrectly handled Winbind NTLM authentication responses. An attacker could possibly use this issue to cause Samba to crash, resulting in a denial of service. (CVE-2022-2127)

Andreas Schneider discovered that Samba incorrectly enforced SMB2 packet signing. A remote attacker could possibly use this issue to obtain or modify sensitive information. This issue only affected Ubuntu 23.04. (CVE-2023-3347)

Florent Saudel and Arnaud Gatignolof discovered that Samba incorrectly handled certain Spotlight requests. A remote attacker could possibly use this issue to cause Samba to consume resources, leading to a denial of service. (CVE-2023-34966, CVE-2023-34967)

Ralph Boehme and Stefan Metzmacher discovered that Samba incorrectly handled paths returned by Spotlight requests. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2023-34968)