# curl 8.20.0

- Product: curl (https://whatsnew.fyi/product/curl)
- Vendor: curl
- Date: 2026-04-29
- Version: 8.20.0
- Original notes: https://curl.se/ch/8.20.0.html
- Permalink: https://whatsnew.fyi/product/curl/releases/8.20.0
- Labels: Platforms: Desktop

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **added** — Add thread pool and queue to lib
- **added** — Add CURLMNWC_CLEAR_ALL to multi.h
- **added** — Add HTTPS-RR use in HTTP/3
- **changed** — Use thread queue for resolving in async-thrdd
- **changed** — Make NTLM disabled by default
- **changed** — Drop support for CMake 3.17 and older
- **changed** — Drop support for c-ares versions before 1.16.0
- **changed** — Make SMB support opt-in
- **changed** — Extend and update curl_ngtcp2 callbacks for 1.22.0+
- **changed** — Use wolfCrypt DES API with wolfSSL in curl_ntlm_core
- **changed** — Support delegating SHA-512/256 to wolfSSL API
- **fixed** — Cap altsvc list at 5,000 entries
- **fixed** — Skip expired entries read from altsvc file
- **fixed** — Fix HTTPS-lookup in asyn-ares when not on port 443
- **fixed** — Fix query counter handling in async-ares
- **fixed** — Fix cookie rejection when tabs in value
- **fixed** — Fix potential infinite loop in curl_get_line when filename is a directory
- **fixed** — Fix memory-leak when doing a second DoH resolve
- **fixed** — Repair CURLINFO_TLS_SESSION in getinfo
- **removed** — Drop RTMP support
- **removed** — Drop the prio field from the altsvc struct

curl / Docs / Releases / Changes in 8.20.0
Related: Daily Snapshots Source repo Release log Pending Release
🠰 8.19.0 all changes 8.21.0 🠲
#### Changes in 8.20.0 - April 29 2026
8.20.0
8.20.0
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: connect async
- asyn-ares: drop orphaned variable references
- asyn-ares: fix HTTPS-lookup when not on port 443
- asyn-thrdd: drop redundant `result` check
- asyn-thrdd: fix clang-tidy unused value warning
- async-ares: fix query counter handling
- 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: adjust/add casts to fix `-Wformat-signedness`
- 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
- build: fix `-Wformat-signedness` by adjusting printf masks
- build: link `bcrypt.lib` via vcxproj files
- build: skip detecting `pipe2()` for Apple targets
- 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
- clang-tidy: enable more checks, fix fallouts
- 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
- configure: tidy up comments
- connect: fix typo on error message
- 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_RTSP_SESSION_ID.md: clarify reuse "dangers"
- CURLOPT_RTSP_SESSION_ID.md: expand the comment
- CURLO

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