Pending RELEASE-NOTES for the upcoming release
This is work in progress and seeing changes before the release goes public on 2026-04-29.
Changes:
- async-thrdd: use thread queue for resolving
- build: make NTLM disabled by default
- cmake: drop support for CMake 3.17 and older
- lib: add thread pool and queue
- lib: drop support for < c-ares 1.16.0
- lib: make SMB support opt-in
- multi.h: add CURLMNWC_CLEAR_ALL
- rtmp: drop support
Bugfixes:
- altsvc: cap the list at 5,000 entries
- altsvc: drop the prio field from the struct
- altsvc: skip expired entries read from file
- asyn-ares: drop orphaned variable references
- asyn-ares: fix HTTPS-lookup when not on port 443
- asyn-thrdd: fix clang-tidy unused value warning
- autotools: limit checksrc target to ignore non-repo test sources
- badwords-all: exit with correct code on errors
- badwords: combine the whitelisting into a single regex
- badwords: detect the the and with with
- badwords: only check comments and strings in source code
- badwords: rework exceptions, fix many of them
- boringssl: fix more coexist cases with Schannel/WinCrypt
- build: assume `snprintf()` in `mprintf`, drop feature check
- build: compiler warning silencing tidy-ups
- build: drop `openssl` module dependency for BoringSSL from `libcurl.pc`
- build: drop duplicate `pthread.h` includes
- build: drop redundant `USE_QUICHE` guards
- build: enable `-Wimplicit-int-enum-cast` compiler warning, fix issues
- cf-https-connect: silence `-Wimplicit-int-enum-cast` with HTTPS-RR
- cf-https-connect: silence `-Wimplicit-int-enum-cast` with HTTPS-RR
- cf-ip-happy: limit concurrent attempts
- cf-socket: avoid low risk integer overflow on ancient Solaris
- cfilters: fix Curl_pollset_poll() return code mixup
- clang-tidy: avoid assignments in `if` expressions
- cmake: add CMake Config-based dependency detection
- cmake: add CMake Config-based dependency detection for c-ares, wolfSSL
- cmake: document functions used from Windows system DLLs
- cmake: enable pthreads for BoringSSL/AWS-LC
- cmake: resolve targets recursively when generating `libcurl.pc`
- cmake: rework binutils ld hack to not read `LOCATION` property
- cmake: silence bad library `Threads::Threads` warning
- cmake: use `AIX` built-in variable (with CMake 4.0+)
- config2setopts: make --capath work in proxy disabled builds
- configure: fix `--with-ngtcp2=<path>` option for crypto libs
- configure: fix LibreSSL ngtcp2 1.15.0+ crypto lib selection logic
- configure: prefer dependency-specific variables over `$withval`
- configure: remove superfluous experimental warning for HTTP/3
- configure: silence useless clang warnings in C89 builds
- cookie: fix rejection when tabs in value
- curl-wolfssl.m4: fix to use the correct value for pkg-config directory
- curl.h: replace macros with C++-friendly method to enforce 3 args
- curl_ctype.h: fix spelling in a couple of locally used macros
- curl_get_line: error out on read errors
- curl_get_line: fix potential infinite loop when filename is a directory
- curl_ngtcp2: extend and update callbacks for 1.22.0+
- curl_ntlm_core: drop redundant PP condition
- curl_ntlm_core: use wolfCrypt DES API with wolfSSL
- curl_setup.h: drop stray/unused `USE_OPENSSL_QUIC` guard
- curl_sha512_256: support delegating to wolfSSL API
- curl_version_info.md: clarify age details
- CURLOPT_HAPROXY_CLIENT_IP.md: mention assumption on data format
- CURLOPT_SOCKS5_AUTH.md: an access property
- CURLOPT_SSL_CTX_FUNCTION.md: expand on effects connection reuse
- CURLOPT_UPLOAD_FLAGS.md: expand
- curlx_now(), prevent zero timestamp
- DEPRECATE: fix minor release number typo
- digest: pass in the user name quoted (as well)
- dnscache: own source file, improvements
- docs/cmdline-opts: tidy up retry-connrefused
- docs/lib: fix typos
- docs: CURLOPT_LOGIN_OPTIONS is a login property
- docs: enable more compiler warnings for C snippets, fix 3 finds
- docs: list more dependencies for running Python HTTP tests
- docs: mention more zip bomb precautions
- docs: minor wording tweaks
- docs: noproxy wants the punycoded hostname version
- docs: SSH host verification is done at connect time
- docs: use the correct CURLOPT_WRITEFUNCTION signature
- doh: fix memory-leak when doing a second DoH resolve
- doh: remove superfluous doh_req check
- examples/websocket: fix to sleep more on Windows
- examples: drop warning silencers no longer hit
- examples: fix typo in comment
- file: init fd to -1 to prevent close fd 0 on early failure
- fopen: for temp files, inherit permissions only for owner
- ftp: do not strdup DATA hostname
- ftp: make the MDTM date parser stricter (again)
- ftp: reject PWD responses containing control characters
- gcc: guard `#pragma diagnostic` in core code for <4.6
- generate.bat: remove extra % from VC11 and VC12 runs
- genserv.pl: make external calls safe
- getinfo: initialize `PureInfo` field `used_proxy`
- gnutls: fix clang-tidy warning with !verbose
- gtls: fail for large files in `load_file()`
- hostip: clear the sockaddr_in6 structure before use
- HSTS: cap the list
- hsts: make the HSTS read callback handle name dupes
- hsts: skip expired HSTS entries read from file
- hsts: when a dupe host adds subdomains, use that
- http2: clear the h2 session at delete
- http2: prevent secure schemes pushed over insecure connections
- http2: return error on OOM in push headers
- HTTP3.md: drop outdated mentions of OpenSSL-QUIC
- http: fix Curl_compareheader for multi value headers
- http: make Curl_compareheader handle multiple commas in header
- imap: reset the UIDVALIDITY state between transfers
- include: drop 'will' from public headers
- INSTALL.md: update Cygwin instructions
- keylog.h: replace literal number with macro in declaration
- keylog: drop unused/redundant includes and guards
- ldap: drop duplicate `ldap_set_option()` on Windows
- ldap: fix to initialize cleartext connection on Windows
- lib: accept larger input to md5/hmac/sha256/sha512 functions
- lib: always use Curl_1st_fatal instead of Curl_1st_err
- lib: make resolving HTTPS DNS records reliable:
- lib: replace `PRI*32` printf masks with C89 ones
- libssh2: fix error handling on quote errors
- libssh: fix 64-bit printf mask for mingw-w64 <=6.0.0
- libssh: fix `-Wsign-compare` in 32-bit builds
- libssh: path length precaution
- libssh: propagate error back in SFTP function
- libtest: drop duplicate include
- location/follow: mention netrc
- man: fix argument type for `CURLSHOPT_[UN]SHARE` options
- mbedtls: fix ECJPAKE matching
- md4, md5: switch to wolfCrypt API in wolfSSL builds
- mk-ca-bundle.pl: make `ca-bundle.crt` timestamp match `certdata.txt`'s
- multi: fix connection retry for non-http
- multi: improve wakeup and wait code
- netrc: find login-less password when user is given in URL
- netrc: remove unused parsenetrc() macro for netrc-disabled
- netrc: skip malformed macdef lines
- openssl channel_binding: lookup digest algorithm without NID
- openssl: drop obsolete SSLv2 logic
- openssl: fix build with 4.0.0-beta1 no-deprecated
- openssl: fix memory leaks in ECH code (OpenSSL 3)
- openssl: trace count of found / imported Windows native CA roots
- OS400: add new definitions to the ILE/RPG binding.
- os400sys: fix typo in comment (symetry -> symmetry)
- parsedate: fix wrong treatment of "military time zones"
- perl: harden external command invocations
- progress: count amount of data "delivered" to application
- protocol.h: fix the CURLPROTO_MASK
- protocol: disable connection reuse for SMB(S)
- protocol: use scheme names lowercase
- proxy: chunked response, error code
- pytest: add additional quiche check for flaky test_05_01
- rand: use `BCryptGenRandom()` in UWP builds
- ratelimit: reset on start
- request: reset resp_trailer in new requests
- scripts: drop redundant double-quotes: `"$var"` -> `$var` (Perl)
- scripts: harden / tidy up more Perl `system()` calls
- sendf: fix CR detection if no LF is in the chunk
- sha256, sha512_256: switch to wolfCrypt API
- sha256: support delegating to wolfSSL API
- share: concurrency handling, easy updates
- share: do bitshifts after the type is checked to be valid
- socks: reject zero-length GSSAPI/SSPI tokens from proxy
- spelling: fix typos
- src: use ftruncate() unconditionally
- sshserver.pl: harden more `system()` calls
- sshserver.pl: pass command-line to `system()` safely
- strerr: correct the strerror_s() return code condition
- sws: fix potential OOB write
- synctime: fix off-by-one read and write to a read-only buffer (Windows)
- test 766: flag as timing-dependent
- test459: switch to mode="warn" for stderr check
- testcurl.pl: replace shell commands with Perl `rmtree()`
- tests/unit/README: describe how to unit test static functions
- tool: check for curlinfo->age when determining if ssh backend
- tool: fix memory mixups
- tool: fix retries in parallel mode
- tool: fix two more allocator mismatches
- tool_cb_hdr: only truncate etags output when regular file
- tool_cb_rea: make waitfd() return void
- tool_cb_wrt: fix no-clobber error handling
- tool_cfgable: free the SSL signature algorithms
- tool_formparse: propagate my_get_line errors when reading headers
- tool_getparam: use correct free function for libcurl memory
- tool_ipfs: accept IPFS gateway URL without set port number
- tool_msgs: avoid null pointer deref for early errors
- tool_operate: actually apply the --parallel-max-host limit
- tool_operate: drop the scheme-guessing in the -G handling
- tool_operate: fix condition for loading `curl-ca-bundle.crt` (Windows)
- tool_operate: fix memory-leak on failed uploads
- tool_operate: fix minor memory-leak on early error
- tool_operhlp: fix `add_file_name_to_url()` result on OOM
- tool_operhlp: iterate through all slashes to find name
- tool_operhlp: propagate low-level OOM in `add_file_name_to_url()`
- tool_setopt: return error on OOM correctly
- tool_urlglob: fix memory-leak on glob range overflow
- top-complexity: prevent filename-based shell injection risk
- transfer: clear the URL pointer in OOM to avoid UAF
- transfer: enable custom methods again on next transfer
- transfer: enhance secure check
- url: do not reuse a non-tls starttls connection if new requires TLS
- url: improve connection reuse on negotiate
- url: init req.no_body in DO so that it works for h2 push
- url: set default upload flags to CURLULFLAG_SEEN
- url: use the socks type for socks proxy
- url: use URL for url even in comments
- urlapi: fix handling of "file:///"
- urlapi: make dedotdotify handle leading dots correctly
- urlapi: verify the last letter of a scheme when set explicitly
- urldata: connection bit ipv6_ip is wrong
- urldata: import port types and conn destination format
- urldata: make hstslist only present in HSTS builds
- urldata: make speeder_c uint32
- urldata: remove trailers_state
- wolfssl: document v5.0.0 (2021-11-01) as minimum required
- wolfssl: fix handling of abrupt connection close
- x509asn1: fix to return error in an error case from `encodeOID()`
- x509asn1: fixed and adapted for ASN1tostr unit testing
- x509asn1: improve encodeOID
Contributors:
Alex Hamilton, am-perip on hackerone, Arkadi Vainbrand, bird on github, BlackFuffey on github, Carlos Henrique Lima Melara, crawfordxx, Cutiapreta on hackerone, Dan Fandrich, Daniel Stenberg, dependabot[bot], Dexter Gerig, Ercan Ermis, fds242 on github, Flavio Amieiro, Geeknik Labs, Greg Kroah-Hartman, Harry Sintonen, Henrique Pereira, Izan on hackerone, James Fuller, Jason Stangroome, John Haugabook, Kai Pastor, Kaixuan Li, lg_oled77c5pua on hackerone, M42kL33 on hackerone, m777m0 on hackerone, Marcel Raad, Martin Dürrmeier, Mehtab Zafar, Michael Hendricks, Michael Kaufmann, Orgad Shaneh, Osama Hamad, Otis Cui Lei, Patrick Monnerat, Ray Satiro, renovate[bot], Richard Tollerton, Rob Crittenden, Samuel Henrique, Scott Boudreaux, Sergey Fedorov, Stefan Eissing, Ted Lyngmo, Viktor Szakats, Vladimír Marek, xkilua on hackerone, Yoshiro Yoneya