SUSE-SU-2024:2636-1

This update for bind fixes the following issues:

Update to release 9.18.28

Security fixes:

• CVE-2024-0760: Fixed a flood of DNS messages over TCP may make the server unstable (bsc#1228255)
• CVE-2024-1737: Fixed BIND's database will be slow if a very large number of RRs exist at the same name (bsc#1228256)
• CVE-2024-1975: Fixed SIG(0) can be used to exhaust CPU resources (bsc#1228257)
• CVE-2024-4076: Fixed assertion failure when serving both stale cache data and authoritative zone content (bsc#1228258)

Changelog:

• Command-line options for IPv4-only (named -4) and IPv6-only (named -6) modes are now respected for zone primaries, also-notify, and parental-agents.
• An RPZ response’s SOA record TTL was set to 1 instead of the SOA TTL, if add-soa was used. This has been fixed.
• When a query related to zone maintenance (NOTIFY, SOA) timed out close to a view shutdown (triggered e.g. by rndc reload), named could crash with an assertion failure. This has been fixed.
• The statistics channel counters that indicated the number of currently connected TCP IPv4/IPv6 clients were not properly adjusted in certain failure scenarios. This has been fixed.
• Some servers that could not be reached due to EHOSTDOWN or ENETDOWN conditions were incorrectly prioritized during server selection. These are now properly handled as unreachable.
• On some systems the libuv call may return an error code when sending a TCP reset for a connection, which triggers an assertion failure in named. This error condition is now dealt with in a more graceful manner, by logging the incident and shutting down the connection.
• Changes to listen-on statements were ignored on reconfiguration unless the port or interface address was changed, making it impossible to change a related listener transport type. That issue has been fixed.
• A bug in the keymgr code unintentionally slowed down some DNSSEC key rollovers. This has been fixed.
• Some ISO 8601 durations were accepted erroneously, leading to shorter durations than expected. This has been fixed
• A regression in cache-cleaning code enabled memory use to grow significantly more quickly than before, until the configured max-cache-size limit was reached. This has been fixed.
• Using rndc flush inadvertently caused cache cleaning to become less effective. This could ultimately lead to the configured max-cache-size limit being exceeded and has now been fixed.
• The logic for cleaning up expired cached DNS records was tweaked to be more aggressive. This change helps with enforcing max-cache-ttl and max-ncache-ttl in a timely manner.
• It was possible to trigger a use-after-free assertion when the overmem cache cleaning was initiated. This has been fixed. New Features:
• A new option signatures-jitter has been added to dnssec-policy to allow signature expirations to be spread out over a period of time.
• The statistics channel now includes counters that indicate the number of currently connected TCP IPv4/IPv6 clients.
• Added RESOLVER.ARPA to the built in empty zones. Feature Changes:
• DNSSEC signatures that are not valid because the current time falls outside the signature inception and expiration dates are skipped instead of causing an immediate validation failure. Security Fixes:
• A malicious DNS client that sent many queries over TCP but never read the responses could cause a server to respond slowly or not at all for other clients. This has been fixed. (CVE-2024-0760)
• It is possible to craft excessively large resource records sets, which have the effect of slowing down database processing. This has been addressed by adding a configurable limit to the number of records that can be stored per name and type in a cache or zone database. The default is 100, which can be tuned with the new max-records-per-type option.
• It is possible to craft excessively large numbers of resource record types for a given owner name, which has the effect of slowing down database processing. This has been addressed by adding a configurable limit to the number of records that can be stored per name and type in a cache or zone database. The default is 100, which can be tuned with the new max-types-per-name option. (CVE-2024-1737)
• Validating DNS messages signed using the SIG(0) protocol (RFC 2931) could cause excessive CPU load, leading to a denial-of-service condition. Support for SIG(0) message validation was removed from this version of named. (CVE-2024-1975)
• Due to a logic error, lookups that triggered serving stale data and required lookups in local authoritative zone data could have resulted in an assertion failure. This has been fixed.
• Potential data races were found in our DoH implementation, related to HTTP/2 session object management and endpoints set object management after reconfiguration. These issues have been fixed.
• When looking up the NS records of parent zones as part of looking up DS records, it was possible for named to trigger an assertion failure if serve-stale was enabled. This has been fixed. (CVE-2024-4076)