CVE-2019-14861

All Samba versions 4.x.x before 4.9.17, 4.10.x before 4.10.11 and 4.11.x before 4.11.3 have an issue, where the (poorly named) dnsserver RPC pipe provides administrative facilities to modify DNS records and zones. Samba, when acting as an AD DC, stores DNS records in LDAP. In AD, the default permissions on the DNS partition allow creation of new records by authenticated users. This is used for example to allow machines to self-register in DNS. If a DNS record was created that case-insensitively matched the name of the zone, the ldb_qsort() and dns_name_compare() routines could be confused into reading memory prior to the list of DNS entries when responding to DnssrvEnumRecords() or DnssrvEnumRecords2() and so following invalid memory as a pointer.

All Samba versions 4.x.x before 4.9.17, 4.10.x before 4.10.11 and 4.11.x before 4.11.3 have an issue, where the (poorly named) dnsserver RPC pipe provides administrative facilities to modify DNS records and zones. Samba, when acting as an AD DC, stores DNS records in LDAP. In AD, the default permissions on the DNS partition allow creation of new records by authenticated users. This is used for example to allow machines to self-register in DNS. If a DNS record was created that case-insensitively matched the name of the zone, the ldb_qsort() and dns_name_compare() routines could be confused into reading memory prior to the list of DNS entries when responding to DnssrvEnumRecords() or DnssrvEnumRecords2() and so following invalid memory as a pointer.

Updated samba packages fix security vulnerabilities:

Malicious servers can cause Samba client code to return filenames containing path separators to calling code (CVE-2019-10218).

When the password contains multi-byte (non-ASCII) characters, the check password script does not receive the full password string (CVE-2019-14833).

Users with the "get changes" extended access right can crash the AD DC LDAP server by requesting an attribute using the range= syntax (CVE-2019-14847).

An authenticated user can crash the DCE/RPC DNS management server by creating records with matching the zone name (CVE-2019-14861).

The DelegationNotAllowed Kerberos feature restriction was not being applied when processing protocol transition requests (S4U2Self), in the AD DC KDC (CVE-2019-14870).

This update for samba fixes the following issues:

• CVE-2019-14861: Fixed a DNSServer RPC server crash, that allowed an authenticated user to crash the DCE/RPC DNS management server by creating records with matching the zone name (bsc#1158108).
• CVE-2019-14870: Fixed a DelegationNotAllowed not being enforced (bsc#1158109).

This update was imported from the SUSE:SLE-15-SP1:Update update project.

These are all security issues fixed in the ctdb-4.14.6+git.182.2205d5224e3-1.1 package on the GA media of openSUSE Tumbleweed.

This update for samba fixes the following issues:

• CVE-2019-14861: Fixed a DNSServer RPC server crash, that allowed an authenticated user to crash the DCE/RPC DNS management server by creating records with matching the zone name (bsc#1158108).
• CVE-2019-14870: Fixed a DelegationNotAllowed not being enforced (bsc#1158109).

This update for samba fixes the following issues:

• CVE-2019-14861: Fixed a DNSServer RPC server crash, that allowed an authenticated user to crash the DCE/RPC DNS management server by creating records with matching the zone name (bsc#1158108).
• CVE-2019-14870: Fixed a DelegationNotAllowed not being enforced (bsc#1158109).

This update for samba to version 4.10.17 fixes the following issues:

• Fixed net command unable to negotiate SMB2; (bsc#1174120);

• Update to 4.10.17

  • CVE-2020-10745: Invalid DNS or NBT queries containing dots use several seconds of CPU each; (bso#14378); (bsc#1173160).
  • CVE-2020-10730: NULL de-reference in AD DC LDAP server when ASQ and VLV combined; (bso#14364); (bsc#1173159).
  • CVE-2020-10760: Fix use-after-free in AD DC Global Catalog LDAP server with paged_result or VLV; (bso#14402); (1173161).
  • CVE-2020-14303: Fix endless loop from empty UDP packet sent to AD DC nbt_server; (bso#14417); (bsc#1173359).
  • CVE-2020-10730: NULL de-reference in AD DC LDAP server when ASQ and VLV combined, ldb: Bump version to 1.5.8; (bso#14364); (bsc#1173159).

• Update to 4.10.16 s3: lib: Paranoia around use of snprintf copying into a fixed-size buffer from a getenv() pointer. lib:util: Fix smbclient -l basename dir; (bso#14345). Malicous SMB1 server can crash libsmbclient; (bso#14366). s3:libads: Fix ads_get_upn(); (bso#14336). docs-xml: Fix usernames in pam_winbind manpages; (bso#14358). Client tools are not able to read gencache anymore since 4.10; (bso#14370).

• Update to 4.10.15

  • CVE-2020-10700: Fix use-after-free in AD DC LDAP server when ASQ and paged_results combined; (bso#14331); (bsc#1169850).
  • CVE-2020-10704: Fix LDAP Denial of Service (stack overflow) in Samba AD DC; (bso#20454); (bsc#1169851).

• Update to 4.10.14 s3: lib: nmblib. Clean up and harden nmb packet processing; (bso#14239). s3: VFS: full_audit. Use system session_info if called from a temporary share definition; (bso#14283). nmblib: Avoid undefined behaviour in handle_name_ptrs(); (bso#20193). dsdb: Correctly handle memory in objectclass_attrs; (bso#14258). auth: Fix CID 1458418 Null pointer dereferences (REVERSE_INULL), auth: Fix CID 1458420 Null pointer dereferences (REVERSE_INULL); (bso#14247). winbind member (source3) fails local SAM auth with empty domain name; (bso#14247). winbindd: Handling missing idmap in getgrgid(); (bso#14265). lib:util: Log mkdir error on correct debug levels; (bso#14253). wafsamba: Do not use 'rU' as the 'U' is deprecated in Python 3.9; (bso#14266). ctdb-tcp: Make error handling for outbound connection consistent; (bso#14274). Starting ctdb node that was powered off hard before results in recovery loop; (bso#14295).

• Update to 4.10.13 s3: libsmb: Ensure SMB1 cli_qpathinfo2() doesn't return an inode number; (bso#14161). s3: utils: smbtree. Ensure we don't call cli_RNetShareEnum() on an SMB1 connection; (bso#14174). s3: libsmb: Ensure return from net_share_enum_rpc() sets cli->raw_status on error; (bso#14176). s3: smbd: SMB2 - Ensure we use the correct session_id if encrypting an interim response; (bso#14189). s3: smbd: Only set xconn->smb1.negprot.done = true after supported_protocols[protocol].proto_reply_fn() succeeds; (bso#14205). pygpo: Use correct method flags; (bso#14209). s3: Remove now unneeded call to cmdline_messaging_context(); (bso#13925). Incomplete conversion of former parametric options; (bso#14069). Fix sync dosmode fallback in async dosmode codepath; (bso#14070). vfs_fruit returns capped resource fork length; (bso#14171). s3:printing: Fix %J substition; (bso#13745). libnet_join: Add SPNs for additional-dns-hostnames entries; (bso#14116). Avoiding bad call flags with python 3.8, using METH_NOARGS instead of zero; (bso#14209). docs-xml/winbindnssinfo: Clarify interaction with idmap_ad etc; (bso#14122). ctdb-tcp: Close inflight connecting TCP sockets after fork; (bso#14175). s4:dirsync: Fix interaction of dirsync and extended_dn controls; (bso#14153). upgradedns: Ensure lmdb lock files linked; (bso#14199). s3: VFS: glusterfs: Reset nlinks for symlink entries during …

Andreas Oster discovered that the Samba DNS management server incorrectly handled certain records. An authenticated attacker could possibly use this issue to crash Samba, resulting in a denial of service. (CVE-2019-14861)

Isaac Boukris discovered that Samba did not enforce the Kerberos DelegationNotAllowed feature restriction, contrary to expectations. (CVE-2019-14870)

USN-4217-1 fixed several vulnerabilities in Samba. This update provides the corresponding update for Ubuntu 14.04 ESM.

Original advisory details:

Andreas Oster discovered that the Samba DNS management server incorrectly handled certain records. An authenticated attacker could possibly use this issue to crash Samba, resulting in a denial of service. (CVE-2019-14861)

Isaac Boukris discovered that Samba did not enforce the Kerberos DelegationNotAllowed feature restriction, contrary to expectations. (CVE-2019-14870)