CVE-2021-43566

All versions of Samba prior to 4.13.16 are vulnerable to a malicious client using an SMB1 or NFS race to allow a directory to be created in an area of the server file system not exported under the share definition. Note that SMB1 has to be enabled, or the share also available via NFS in order for this attack to succeed.

All versions of Samba prior to 4.13.16 are vulnerable to a malicious client using an SMB1 or NFS race to allow a directory to be created in an area of the server file system not exported under the share definition. Note that SMB1 has to be enabled, or the share also available via NFS in order for this attack to succeed.

All versions of Samba prior to 4.13.16 are vulnerable to a malicious client using an SMB1 or NFS race to allow a directory to be created in an area of the server file system not exported under the share definition. Note that SMB1 has to be enabled, or the share also available via NFS in order for this attack to succeed.

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

Security Fix(es):

All versions of Samba prior to 4.13.16 are vulnerable to a malicious client using an SMB1 or NFS race to allow a directory to be created in an area of the server file system not exported under the share definition. Note that SMB1 has to be enabled, or the share also available via NFS in order for this attack to succeed.(CVE-2021-43566)

All versions of Samba prior to 4.13.16 are vulnerable to a malicious client using an SMB1 or NFS race to allow a directory to be created in an area of the server file system not exported under the share definition. Note that SMB1 has to be enabled, or the share also available via NFS in order for this attack to succeed.

• CVE-2021-43566: fix mkdir_internal() symlink race that allowed an SMB1 or NFS client to create a directory outside the exported share; pin the parent via vfs_ChDir() and validate the relative path before SMB_VFS_MKDIR()

• CVE-2021-43566: fix mkdir_internal() symlink race that allowed an SMB1 or NFS client to create a directory outside the exported share; pin the parent via vfs_ChDir() and validate the relative path before SMB_VFS_MKDIR()

• CVE-2021-43566: fix mkdir_internal() symlink race that allowed an SMB1 or NFS client to create a directory outside the exported share; pin the parent via vfs_ChDir() and validate the relative path before SMB_VFS_MKDIR()

• CVE-2021-44141: Information leak via symlinks of existance of files or directories outside of the exported share; (bso#14911); (bsc#1193690);
• CVE-2021-44142: Out-of-bounds heap read/write vulnerability in VFS module vfs_fruit allows code execution; (bso#14914); (bsc#1194859);
• CVE-2022-0336: Samba AD users with permission to write to an account can impersonate arbitrary services; (bso#14950); (bsc#1195048);

samba was updated to 4.15.4 (jsc#SLE-23329);

• Duplicate SMB file_ids leading to Windows client cache poisoning; (bso#14928);
• Failed to parse NTLMv2_RESPONSE length 95 - Buffer Size Error - NT_STATUS_BUFFER_TOO_SMALL; (bso#14932);
• kill_tcp_connections does not work; (bso#14934);
• Can't connect to Windows shares not requiring authentication using KDE/Gnome; (bso#14935);
• smbclient -L doesn't set 'client max protocol' to NT1 before calling the 'Reconnecting with SMB1 for workgroup listing' path; (bso#14939);
• Cross device copy of the crossrename module always fails; (bso#14940);
• symlinkat function from VFS cap module always fails with an error; (bso#14941);
• Fix possible fsp pointer deference; (bso#14942);
• Missing pop_sec_ctx() in error path inside close_directory(); (bso#14944);
• 'smbd --build-options' no longer works without an smb.conf file; (bso#14945);

Samba was updated to version 4.15.3

• CVE-2021-43566: Symlink race error can allow directory creation outside of the exported share; (bsc#1139519);
• CVE-2021-20316: Symlink race error can allow metadata read and modify outside of the exported share; (bsc#1191227);

• Reorganize libs packages. Split samba-libs into samba-client-libs, samba-libs, samba-winbind-libs and samba-ad-dc-libs, merging samba public libraries depending on internal samba libraries into these packages as there were dependency problems everytime one of these public libraries changed its version (bsc#1192684). The devel packages are merged into samba-devel.
• Rename package samba-core-devel to samba-devel
• Update the symlink create by samba-dsdb-modules to private samba ldb modules following libldb2 changes from /usr/lib64/ldb/samba to /usr/lib64/ldb2/modules/ldb/samba

krb5 was updated to 1.16.3 to 1.19.2

• Fix a denial of service attack against the KDC encrypted challenge code; (CVE-2021-36222);
• Fix a memory leak when gss_inquire_cred() is called without a credential handle.

Changes from 1.19.1:

• Fix a linking issue with Samba.
• Better support multiple pkinit_identities values by checking whether certificates can be loaded for each value.

Changes from 1.19

Administrator experience

• When a client keytab is present, the GSSAPI krb5 mech will refresh credentials even if the current credentials were acquired manually.
• It is now harder to accidentally delete the K/M entry from a KDB. Developer experience
• gss_acquire_cred_from() now supports the 'password' and 'verify' options, allowing credentials to be acquired via password and verified using a keytab key.
• When an application accepts a GSS security context, the new GSS_C_CHANNEL_BOUND_FLAG will be set if the initiator and acceptor both provided matching channel bindings.
• Added the GSS_KRB5_NT_X509_CERT name type, allowing S4U2Self requests to identify the desired client principal by certificate.
• PKINIT certauth modules can now cause the hw-authent flag to be set in issued tickets.
• The krb5_init_creds_step() API will now issue the same password expiration warnings as krb5_get_init_creds_password(). Protocol evolution
• Added client and KDC support for Microsoft's Resource-Based Constrained Delegation, which allows cross-realm S4U2Proxy requests. A third-party database module is required for KDC support.
• kadmin/admin is now the preferred server principal name for kadmin connections, and the host-based form is no longer created by default. The client will still try the host-based form as a…

• CVE-2021-44141: Information leak via symlinks of existance of files or directories outside of the exported share; (bso#14911); (bsc#1193690);
• CVE-2021-44142: Out-of-bounds heap read/write vulnerability in VFS module vfs_fruit allows code execution; (bso#14914); (bsc#1194859);
• CVE-2022-0336: Samba AD users with permission to write to an account can impersonate arbitrary services; (bso#14950); (bsc#1195048);

samba was updated to 4.15.4 (jsc#SLE-23329);

• Duplicate SMB file_ids leading to Windows client cache poisoning; (bso#14928);
• Failed to parse NTLMv2_RESPONSE length 95 - Buffer Size Error - NT_STATUS_BUFFER_TOO_SMALL; (bso#14932);
• kill_tcp_connections does not work; (bso#14934);
• Can't connect to Windows shares not requiring authentication using KDE/Gnome; (bso#14935);
• smbclient -L doesn't set 'client max protocol' to NT1 before calling the 'Reconnecting with SMB1 for workgroup listing' path; (bso#14939);
• Cross device copy of the crossrename module always fails; (bso#14940);
• symlinkat function from VFS cap module always fails with an error; (bso#14941);
• Fix possible fsp pointer deference; (bso#14942);
• Missing pop_sec_ctx() in error path inside close_directory(); (bso#14944);
• 'smbd --build-options' no longer works without an smb.conf file; (bso#14945);

Samba was updated to version 4.15.3

• CVE-2021-43566: Symlink race error can allow directory creation outside of the exported share; (bsc#1139519);
• CVE-2021-20316: Symlink race error can allow metadata read and modify outside of the exported share; (bsc#1191227);

• Reorganize libs packages. Split samba-libs into samba-client-libs, samba-libs, samba-winbind-libs and samba-ad-dc-libs, merging samba public libraries depending on internal samba libraries into these packages as there were dependency problems everytime one of these public libraries changed its version (bsc#1192684). The devel packages are merged into samba-devel.
• Rename package samba-core-devel to samba-devel
• Update the symlink create by samba-dsdb-modules to private samba ldb modules following libldb2 changes from /usr/lib64/ldb/samba to /usr/lib64/ldb2/modules/ldb/samba

krb5 was updated to 1.16.3 to 1.19.2

• Fix a denial of service attack against the KDC encrypted challenge code; (CVE-2021-36222);
• Fix a memory leak when gss_inquire_cred() is called without a credential handle.

Changes from 1.19.1:

• Fix a linking issue with Samba.
• Better support multiple pkinit_identities values by checking whether certificates can be loaded for each value.

Changes from 1.19

Administrator experience

• When a client keytab is present, the GSSAPI krb5 mech will refresh credentials even if the current credentials were acquired manually.
• It is now harder to accidentally delete the K/M entry from a KDB. Developer experience
• gss_acquire_cred_from() now supports the 'password' and 'verify' options, allowing credentials to be acquired via password and verified using a keytab key.
• When an application accepts a GSS security context, the new GSS_C_CHANNEL_BOUND_FLAG will be set if the initiator and acceptor both provided matching channel bindings.
• Added the GSS_KRB5_NT_X509_CERT name type, allowing S4U2Self requests to identify the desired client principal by certificate.
• PKINIT certauth modules can now cause the hw-authent flag to be set in issued tickets.
• The krb5_init_creds_step() API will now issue the same password expiration warnings as krb5_get_init_creds_password(). Protocol evolution
• Added client and KDC support for Microsoft's Resource-Based Constrained Delegation, which allows cross-realm S4U2Proxy requests. A third-party database module is required for KDC support.
• kadmin/admin is now the preferred server principal name for kadmin connections, and the host-based form is no longer created by default. The client will still try the host-based form as a…

This update contains a major security update for Samba.

samba has received security fixes:

• CVE-2021-44141: Information leak via symlinks of existance of files or directories outside of the exported share (bsc#1193690);
• CVE-2021-44142: Out-of-bounds heap read/write vulnerability in VFS module vfs_fruit allows code execution (bsc#1194859);
• CVE-2022-0336: Samba AD users with permission to write to an account can impersonate arbitrary services (bsc#1195048);

samba was updated to version 4.15.4; (jsc#SLE-23330);

• CVE-2021-43566: Symlink race error can allow directory creation outside of the exported share; (bso#13979); (bsc#1139519);
• CVE-2021-20316: Symlink race error can allow metadata read and modify outside of the exported share; (bso#14842); (bsc#1191227);

• Build samba with embedded talloc, pytalloc, pytalloc-util, tdb, pytdb, tevent, pytevent, ldb, pyldb and pyldb-util libraries. The tdb and ldb tools are installed in /usr/lib[64]/samba/bin and their manpages in /usr/lib[64]/samba/man

  This avoids removing old functionality.

samba was updated to 4.15.4:

• Duplicate SMB file_ids leading to Windows client cache poisoning; (bso#14928);
• Failed to parse NTLMv2_RESPONSE length 95 - Buffer Size Error - NT_STATUS_BUFFER_TOO_SMALL; (bso#14932);
• kill_tcp_connections does not work; (bso#14934);
• Can't connect to Windows shares not requiring authentication using KDE/Gnome; (bso#14935);
• smbclient -L doesn't set 'client max protocol' to NT1 before calling the 'Reconnecting with SMB1 for workgroup listing' path; (bso#14939);
• Cross device copy of the crossrename module always fails; (bso#14940);
• symlinkat function from VFS cap module always fails with an error; (bso#14941);
• Fix possible fsp pointer deference; (bso#14942);
• Missing pop_sec_ctx() in error path inside close_directory(); (bso#14944);
• 'smbd --build-options' no longer works without an smb.conf file; (bso#14945);

• Reorganize libs packages. Split samba-libs into samba-client-libs, samba-libs, samba-winbind-libs and samba-ad-dc-libs, merging samba public libraries depending on internal samba libraries into these packages as there were dependency problems everytime one of these public libraries changed its version (bsc#1192684). The devel packages are merged into samba-devel.
• Rename package samba-core-devel to samba-devel
• Update the symlink create by samba-dsdb-modules to private samba ldb modules following libldb2 changes from /usr/lib64/ldb/samba to /usr/lib64/ldb2/modules/ldb/samba

sssd was updated:

• Build with the newer samba versions; (jsc#SLE-23330);
• Fix a dependency loop by moving internal libraries to sssd-common package; (bsc#1182058);

p11-kit was updated:

Update to 0.23.2; (jsc#SLE-23330);

• Fix forking issues with libffi
• Fix various crashes in corner cases
• Updated translations
• Build fixes

• Fix multiple integer overflows in rpc code (bsc#1180064 CVE-2020-29361):
• Add support for CKA_NSS_{SERVER,EMAIL}_DISTRUST_AFTER (bsc#1187993)

ca-certificates was updated:

• p11-kit 0.23.1 supports pem-directory-hash. (jsc#SLE-23330)

This update also ships:

• libnettle 3.1 and gnutls 3.4.17 as parallel libraries to meet the requires of the newer samba.

apparmor was updated:

• Update samba apparmor profiles for samba 4.15 (jsc#SLE-23330);

yast2-samba-client was updated:

• With latest versions of samba (>=4.15.0) calling 'net ads lookup' with '-U%' fails; (boo#1193533).
• yast-samba-client fails to join if /etc/samba/smb.conf or /etc/krb5.conf don't exist; (bsc#1089938)
• Do not stop nmbd while nmbstatus is running, it is not necessary anymore; (bsc#1158916);

Orange Tsai discovered that the Samba vfs_fruit module incorrectly handled certain memory operations. A remote attacker could use this issue to cause Samba to crash, resulting in a denial of service, or possibly execute arbitrary code as root. (CVE-2021-44142)

Michael Hanselmann discovered that Samba incorrectly created directories. In certain configurations, a remote attacker could possibly create a directory on the server outside of the shared directory. (CVE-2021-43566)

Kees van Vloten discovered that Samba incorrectly handled certain aliased SPN checks. A remote attacker could possibly use this issue to impersonate services. (CVE-2022-0336)