unbound-1.16.2

[Bruce Dubbs]

New point version.

[pierre]

Unbound 1.16.2

Features

Merge #718: Introduce infra-cache-max-rtt option to config max retransmit timeout.

Bug Fixes

• Fix the novel ghost domain issues CVE-2022-30698 and CVE-2022-30699.
• Fix bug introduced in 'improve val_sigcrypt.c::algo_needs_missing for one loop pass'.
• Merge PR #668 from Cristian Rodríguez: Set IP_BIND_ADDRESS_NO_PORT on outbound tcp sockets.
• Fix verbose EDE error printout.
• Fix dname count in sldns parse type descriptor for SVCB and HTTPS.
• For windows crosscompile, fix setting the IPV6_MTU socket option equivalent (IPV6_USER_MTU); allows cross compiling with latest cross-compiler versions.
• Merge PR 714: Avoid treat normal hosts as unresponsive servers. And fixup the lock code.
• iana portlist update.
• Update documentation for 'outbound-msg-retry:'.
• Tests for ghost domain fixes.

Novel "ghost domain names" attack by updating almost expired delegation information

Date: 2022-08-01
CVE: CVE-2022-30699
Credit: Xiang Li (Network and Information Security Lab, Tsinghua University)
Affects: Unbound up to and including version 1.16.1
Not affected: Other versions
Severity: Medium
Impact: Remote attackers can trigger continued resolvability of revoked domain names
Solution: Download patched version of Unbound, or apply the patch manually

NLnet Labs Unbound, up to and including version 1.16.1, is vulnerable to a novel type of the "ghost domain names" attack. The vulnerability works by targeting an Unbound instance. Unbound is queried for a rogue domain name when the cached delegation information is about to expire. The rogue nameserver delays the response so that the cached delegation information is expired. Upon receiving the delayed answer containing the delegation information, Unbound overwrites the now expired entries. This action can be repeated when the delegation information is about to expire making the rogue delegation information ever-updating. From version 1.16.2 on, Unbound stores the start time for a query and uses that to decide if the cached delegation information can be overwritten.

Unbound 1.16.2 contains a patch. If you cannot upgrade you can also apply the patch manually. To do this, apply the patch on the Unbound source directory with patch -p1 < patch_CVE-2022-30698_CVE-2022-30699.diff and then run make install to install Unbound.

This is a shared patch with CVE-2022-30698 below
Novel "ghost domain names" attack by introducing subdomain delegations

Date: 2022-08-01
CVE: CVE-2022-30698
Credit: Xiang Li (Network and Information Security Lab, Tsinghua University)
Affects: Unbound up to and including version 1.16.1
Not affected: Other versions
Severity: Medium
Impact: Remote attackers can trigger continued resolvability of revoked domain names
Solution: Download patched version of Unbound, or apply the patch manually

NLnet Labs Unbound, up to and including version 1.16.1 is vulnerable to a novel type of the "ghost domain names" attack. The vulnerability works by targeting an Unbound instance. Unbound is queried for a subdomain of a rogue domain name. The rogue nameserver returns delegation information for the subdomain that updates Unbound's delegation cache. This action can be repeated before expiry of the delegation information by querying Unbound for a second level subdomain which the rogue nameserver provides new delegation information. Since Unbound is a child-centric resolver, the ever-updating child delegation information can keep a rogue domain name resolvable long after revocation. From version 1.16.2 on, Unbound checks the validity of parent delegation records before using cached delegation information.

Unbound 1.16.2 contains a patch. If you cannot upgrade you can also apply the patch manually. To do this, apply the patch on the Unbound source directory with patch -p1 < patch_CVE-2022-30698_CVE-2022-30699.diff and then run make install to install Unbound.

This is a shared patch with CVE-2022-30699 above

[pierre]

Updated at bd81aa637d. Leaving open for SA.

[pierre]

SA at commit be5e1bfba2e61 in www repository