- Fix to check for invalid http content length and chunk size,
and to check the RR rdata field lengths when decompressing and
inserting RRs from an authority zone transfer. This stops
large memory use and heap buffer-overflow read errors. Thanks
to Haruto Kimura (Stella) for the report.
- For #278: fast_reload can reload tls-service-key, tls-service-pem
and tls-cert-bundle changes. It checks the modification time of
the tls-service-key and tls-service-pem files for update.
- Fix #278: DoT: complete unbound restart required on certificate
renew. Fix so that a reload checks if the files have changed, and
if so, reload the contexts. Also for DoH, DoQ and outgoing DoT.
- Fix to ignore out-of-zone DNAME records for CNAME synthesis. Thanks
to Yuxiao Wu, Yiyi Wang, Zhang Chao, Baojun Liu, and Haixin Duan from
Tsinghua University.
Arunabha Das [Mon, 9 Mar 2026 12:53:52 +0000 (18:23 +0530)]
Apply cache TTL policy to DNAME and synthesized CNAME on wire path (#1418)
When the scrubber synthesizes a CNAME from a DNAME (authority omits CNAME),
apply cache-min-ttl/cache-max-ttl to both DNAME and synthesized CNAME in
msg_parse so they stay equal and respect config (RFC 6672).
- iterator/iter_scrub.c: In synth_cname_rrset(), clamp TTL to [MIN_TTL,
MAX_TTL] when !SERVE_ORIGINAL_TTL and write back to both synth CNAME
and DNAME rrset. Removes FIXME.
- Fix for DNS Rebinding Bypass via SVCB/HTTPS Records in Unbound.
Thanks to Kunta Chu, School of Software, Tsinghua University,
Taofei Guo, Peking University, and Jianjun Chen, Institute for
Network Sciences and Cyberspace, Tsinghua University for the
report. The private-address option is fixed to also elide
SVCB and HTTPS records that match the filter.
Arunabha Das [Tue, 3 Mar 2026 07:51:31 +0000 (13:21 +0530)]
Allow synthesized DNAME TTL=0 to be served from cache within grace period (#1411)
* Allow synthesized DNAME TTL=0 to be served from cache within grace period
Addresses doc/TODO: cache TTL=0 packets properly for synthesis.
- rrset_cache_lookup: allow TTL=0 DNAME within 1s grace for synthesis
- synth_dname_msg: support PACKED_RRSET_UPSTREAM_0TTL, return TTL=0 to client
Reduces recursion when authoritative servers return DNAME with TTL=0 (RFC 2308).
Client response still correctly returns TTL=0.
Note: Test with proper TTL=0 DNSSEC RRSIGs omitted - requires ldns-signzone
to generate valid signatures for TTL=0 RRsets.
* Add iter_dname_ttl0.rpl replay test for DNAME TTL=0
Tests signed DNAME with TTL=0 and RRSIG Original TTL=0 (RFC 4034).
Verifies end-to-end handling of TTL=0 DNAME responses.
- Fix validator to set unchecked when validation recursion
requests are passed. The edns subnet module checks if validation
is needed for a cache response, and set the validator to protect
the cache with validation for non-subnet lookups.
- Fix #1404: Priming the root key fails after loading ipfire.org RPZ
zones. Fixed by including the ZONEMD RRtype in the list of types to
ignore for RPZ zones. Analysis and patch provided by ummeegge.
Changelog note and documentation for #1401.
- Merge #1401: Add a new build-time option for system TLS.
The --enable-system-tls flag enables the
tls-use-system-policy-versions setting by default.
Petr Menšík [Mon, 9 Feb 2026 14:57:16 +0000 (15:57 +0100)]
Add a new build-time option for system TLS (#1401)
We want to use crypto-policy provided configuration always in our
builds. Allow changing the default of tls-use-system-policy-versions at
build time by a simple configure parameter.
- Fix local privilege escalation on Windows. Thanks to Hao Huang
for the report. The OpenSSL init calls are set to not load
the openssl.cnf file when compiled for Windows.
Changelog entry for #1396:
- Merge #1396: Log Linux thread ID.
- On Linux systems log the system-wide unique thread ID instead of
Unbound's internal thread counter.
- Introduce the 'log-thread-id' configuration option to manage logging
the system-wide Linux thread ID for easier debugging with system
tools.
Petr Menšík [Thu, 8 Jan 2026 13:12:32 +0000 (14:12 +0100)]
Do not initialize quic_table unless it is enabled (#1381)
* Do not initialize quic_table unless it is enabled
Fedora in FIPS mode might fail to initialize ngtcp2 library, because
some ciphers desired are not available.
Make it possible to skip initialization by setting explicitly quic_port
to 0. Unless we have some listeners for port 853 configured, skip its
initialization as well.
- Fix edns subnet, that scope zero queries, when there is a
subquery without subnet, and the forward-no-cache or
stub-no-cache option is set, it is not stored in cache due to
the forward or stub option.
This has the changelog entry and test.
- Fix edns subnet, that scope zero queries, when there is a
subquery without subnet, and the forward-no-cache or
stub-no-cache option is set, it is not stored in cache due to
the forward or stub option.
- Fix http2 drop handling to clear the postpone_drop state so that
other streams on the http2 session are not affected by a drop,
and can clean up properly if also dropped. Fix http2 send reply
so that when there is a send failure is does not recurse into
the mesh functions and also does not drop the connection due to
the condition of one stream.
- Additional fix for CVE-2025-11411 (possible domain hijacking attack),
to include YXDOMAIN and non-referral nodata answers in the mitigation as
well, reported by TaoFei Guo from Peking University, Yang Luo and JianJun
Chen from Tsinghua University.
Changelog note for #1375, and lock for lockchecks and ifdef for compile fix.
- Merge #1375: Copy DNSTAP changes from daemon to workers after
fast_reload.
smeddlep [Thu, 13 Nov 2025 14:42:44 +0000 (14:42 +0000)]
Copy DNSTAP changes from daemon to workers after fast_reload (#1375)
- On fast_reload, the identity and version strings are always freed and
reallocated as part of dt_apply_cfg(). Add fr_worker_pickup_dnstap_changes()
to copy any changes from daemon to workers.
Robert Edmonds [Thu, 13 Nov 2025 08:33:05 +0000 (03:33 -0500)]
Mesh reply counters (#1374)
* Statistics counter for number of queries dropped by limit on reply addresses
Request list entries can be associated with multiple pending "reply
addresses". Basically each request list entry keeps its own list of
clients that should receive the response once the recursion is finished.
This requires keeping allocations around for each client, and there is
a global limit on the number of *additional* reply addresses that can
be allocated. (Each new request list entry seems to get its own initial
reply address which is not counted against the limit.)
This commit adds a statistics counter "num_queries_replyaddr_limit" that
counts the number of incoming client queries that have been dropped due
to the restriction on allocating additional reply addresses. This allows
distinguishing these drops from other kinds of drops.
* Statistics counter for number of mesh reply entries
Request list entries can be associated with multiple pending "reply
addresses". Since there is a limit on the number of additional reply
addresses that can be allocated which can cause incoming queries to be
dropped if exceeded, it would be nice to be able to track this number.
This commit basically exports the mesh_area's internal counter
`num_reply_addrs` as "threadX.requestlist.current.replies" /
"total.requestlist.current.replies".
- Fix #1366: Infra cache does not work correctly for NAT64, by
moving the NAT64 synthesis from the iterator when selecting a target
address, to the delegation point itself when adding target
addresses.
- Fix #1165, document the possible circular dependency when using
host names instead of IP addresses for name servers in stub/forward
zones and log a warning when spotted in the configuration.