Erlang/OTP 29.0.6

The compiler-10.0.4 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20312

Related Id(s):

GH-11494, PR-11503

compiler: Fix bug in beam_types:subtract/2 for bitstrings

Full runtime dependencies of compiler-10.0.4

crypto-5.1, erts-13.0, kernel-8.4, stdlib-8.0

The crypto-5.9.3 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20333

Related Id(s):

GH-11511, PR-11513

Fixed type mismatch between ErlNifUInt64 and uint64_t in crypto NIF that caused incompatible-pointer warnings on macOS arm64 when passing DH parameters to OpenSSL.

Full runtime dependencies of crypto-5.9.3

erts-9.0, kernel-6.0, stdlib-3.9

The eldap-1.3.1 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20345

Related Id(s):

PR-11538

eldap referral URL parsing now rejects a port component longer than 5 digits instead of attempting to convert an arbitrarily large digit string to an integer.

Full runtime dependencies of eldap-1.3.1

asn1-3.0, erts-6.0, kernel-3.0, ssl-5.3.4, stdlib-3.4

The erl_interface-5.8.2 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20324

Related Id(s):

PR-11492

erl_interface: Fix buffer leak and state corruption on ei_x_buff realloc failure

The erts-17.0.6 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20135

Related Id(s):

GH-11052, PR-11463

No-suspend port command signals (i.e. port command signals sent using the erlang:port_command/3 BIF or the erlang:send/3 BIF with the nosuspend option) were not aborted properly in all scenarios which could leave the port queue in a busy state indefinitely. Also asynchronously sent no-suspend command signals (i.e, port command signals sent using the erlang:send/3 BIF with the nosuspend option) could sometimes be delivered even though the port was busy.

OTP-20274

Related Id(s):

GH-11278, PR-11298

erts: Fix missing exit_status caused by SIGCHLD race

OTP-20278

Related Id(s):

GH-11419, PR-11429

erts: Fix bug in is_in_range instruction for x86 JIT

OTP-20281

Related Id(s):

GH-11404, PR-11425

Fixed bug in binary_to_term that could cause emulator crash for specific terms in specific process states (reductions left).

OTP-20282

Related Id(s):

PR-11428

erts: Fix crash with term_to_iovec/2 for large binary

OTP-20286

Related Id(s):

GH-11416, PR-11417

A distributed priority send larger than 32 KiB to a process alias caused the receiving runtime system to crash.

OTP-20300

Related Id(s):

PR-11485

Priority message queue markers were sometimes installed in the message queue even when no priority messages could be received. As a result, the two markers had to be traversed unnecessarily when scanning the message queue, introducing a small but avoidable overhead.

OTP-20319

Related Id(s):

PR-11509

A monitor of time_offset co-created with a process alias (monitor(time_offset, clock_service, [{alias, UnaliasOpt}])) either crashed the runtime system or did not work. This bug was introduced in OTP 25.0.

OTP-20330

Related Id(s):

PR-11521

A process alias was erroneously created when a remote spawn_request() operation with a {monitor, [{alias, explicit_unalias}]} option failed with noconnection reason.

OTP-20334

Related Id(s):

PR-11533, CVE-2026-75538

A gen_tcp socket using the inet driver and {packet,4} had a bug if receiving a packet with size just below INT_MAX.

That packet size wrapped in size calculations and made the received data overwrite its allocation and trash allocator metadata and subsequent block(s), causing the VM to crash.

This made it possible for anyone to remotely crash an Erlang node that used {packet,4} on a reachable socket.

This bug has been corrected.

Full runtime dependencies of erts-17.0.6

kernel-9.0, sasl-3.3, stdlib-4.1

The inets-9.7.2 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20264

Related Id(s):

PR-11546

The dets and mnesia mod_auth backends used a key that did not include the directory path, so all require_user/require_group records collapsed into one per-listener namespace. A user authorized for one protected directory could authenticate against any other protected directory served by the same listener. {path, Directory} is now included in the auth backend key, scoping records per directory as documented.

OTP-20268

Related Id(s):

PR-11547

Requests specifying both Transfer-Encoding and Content-Length headers are now rejected with 400 Bad Request, per RFC 9112 Section 6.3. Previously such requests could be used for CL.TE request-smuggling/desync attacks against reverse proxies in front of httpd.

OTP-20269

Related Id(s):

PR-11544

httpd accepted the obsolete header line-folding syntax (RFC 9112 Section 5.2, a continuation line beginning with space/tab), silently treating the folded continuation as a separate header. This allowed CL.TE-style request smuggling when httpd was placed behind a folding-aware proxy. Such requests are now rejected with 400 Bad Request.

OTP-20270

Related Id(s):

PR-11545

A header such as Content-Length : 6 (whitespace before the colon) was previously silently dropped, causing the content length to default to 0 and the body bytes to be misinterpreted as a pipelined request (CL.0 smuggling). Per RFC 7230 Section 3.2.4, such headers are now rejected with 400 Bad Request.

OTP-20271

Related Id(s):

PR-11543

A new httpd option request_timeout (default 60 seconds, renamed from the interim max_body_read_timeout) bounds the idle time between reads of a request body/message. The server now also sends 408 Request Timeout when the min_bytes_per_second floor is hit, and keep_alive_timeout measurement was corrected so the timer is cancelled as soon as new data arrives rather than only after full header parsing; keep_alive_timeout and request_timeout now also accept infinity to disable the timeout.

OTP-20279

Related Id(s):

PR-11542

mod_auth, mod_security, and mod_get compared resolved filesystem paths against configured protected-directory patterns without normalizing repeated slashes or filesystem case. On case-insensitive filesystems (macOS, Windows) or with repeated slashes, a request could resolve to a protected resource while evading the directory match. Paths are now canonicalized (slash-collapsed, and case-normalized when the filesystem is case-insensitive) before the authorization decision.

OTP-20306

Related Id(s):

PR-11539

A request with an invalid chunked transfer-encoding chunk size previously caused the httpd connection handler to hang indefinitely without requiring further input from the client. This leaked a process per request and could be used to exhaust server resources (denial of service). Invalid chunk sizes are now rejected immediately with an error response, and the connection is closed.

OTP-20307

Related Id(s):

PR-11540

max_body_size was previously enforced only after a complete chunk had been received, allowing a single oversized chunk to be buffered in full before the limit was checked — undermining the memory-exhaustion protection the option is meant to provide. The limit is now enforced incrementally as chunk data arrives, rejecting the request as soon as the configured size is exceeded.

OTP-20308

Related Id(s):

PR-11541

The documented default of 150 for the max_clients option was not applied by the implementation, allowing an unbounded number of concurrent clients to connect regardless of configuration. The default is now correctly enforced.

OTP-20342

Related Id(s):

PR-11548

Fixed a bug where httpd failed to start when configured with {socket_type, {ip_comm, SockOpts}} and a fixed (non-zero) port.

OTP-20343

Related Id(s):

PR-11538

httpc now enforces a limit on the total size of response headers and response body, preventing unbounded memory allocation when connecting to a malicious or malfunctioning server. The new max_header_size and max_body_size request options can be used to override the default limit (10240 bytes for headers). Additionally, httpc now validates that the Content-Length header contains only digits before use, avoiding a crash on malformed responses.

Full runtime dependencies of inets-9.7.2

erts-14.0, kernel-9.0, mnesia-4.12, public_key-1.13, runtime_tools-1.8.14, ssl-9.0, stdlib-5.0, stdlib-6.0

The megaco-4.9.2 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20234

Related Id(s):

PR-11325

Numeric fields in megaco text-encoded messages are now validated for digit-string length before integer conversion, improving robustness of the text decoder. Per-field digit limits based on the H.248.1 ASN.1 type constraints are enforced (e.g., 10 digits for UINT32, 2 digits for timer values), along with a 100 KB overall message size cap at the scanner entry point. The binary (BER/PER) codec is not affected.

Full runtime dependencies of megaco-4.9.2

asn1-3.0, debugger-4.0, erts-12.0, et-1.5, kernel-8.0, runtime_tools-1.8.14, stdlib-2.5

The mnesia-4.26.2 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20347

Related Id(s):

PR-11517

A transaction iterating a table (first/1, last/1, next/2, prev/2, select, select_reverse on non-ordered_set) leaked a safe_fixtable hold when the coordinator was killed by an external signal. The table remained fixed for the lifetime of the node, preventing space reclamation of deleted objects.

OTP-20351

Related Id(s):

PR-11554

Fixed a race condition where mnesia_controller could crash if a table was deleted while mnesia:set_master_nodes/2 was being processed.

Full runtime dependencies of mnesia-4.26.2

erts-9.0, kernel-5.3, stdlib-5.0

The public_key-1.21.5 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20321

Related Id(s):

GH-11240, PR-11358

Retain lost CommonName length relaxation.

Full runtime dependencies of public_key-1.21.5

asn1-5.0, crypto-5.8, erts-13.0, kernel-8.0, stdlib-4.0

The snmp-5.20.5 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20346

Related Id(s):

PR-11538

The SNMP PDU decoder now bounds the byte length accepted for INTEGER, Counter32, Gauge32/Unsigned32, TimeTicks, and Counter64 values during decoding (4, 5, 5, 5, and 9 bytes respectively, matching the SMIv2 value ranges), instead of accepting an arbitrarily large byte string and converting it to an integer.

Full runtime dependencies of snmp-5.20.5

asn1-5.4, crypto-4.6, erts-12.0, kernel-8.0, mnesia-4.12, runtime_tools-1.8.14, stdlib-5.0

The ssh-6.0.5 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20284

Related Id(s):

PR-11437

Fixed a bug where multiple subsystem requests could succeed on same ssh channel which is forbidden by RFC 4254 §6.5

Full runtime dependencies of ssh-6.0.5

crypto-5.7, erts-14.0, kernel-10.3, public_key-1.6.1, runtime_tools-1.15.1, stdlib-8.0

Note! The ssl-11.7.5 application cannot be applied independently of other applications on an arbitrary OTP 29 installation.

   On a full OTP 29 installation, also the following runtime
   dependency has to be satisfied:
   -- public_key-1.21.1 (first satisfied in OTP 29.0.1)

OTP-20350

Related Id(s):

ERIERL-1354, PR-11553

Debugging keylog_hs callback used for logging handshake secrets on failed connections swapped the argument order in logging function confusing server and client side. The bug was introduced in OTP 28.5

OTP-20289

Related Id(s):

PR-11478

Hardening improvements of the ssl application.

TLS distribution now defaults to TLS-1.3 instead of TLS-1.2 (TLS-1.2 is kept as fallback for rolling upgrades).

TLS-1.2 server with {verify, verify_peer} now defaults reuse_sessions to false to mitigate the Triple Handshake attack (RFC 7627). Set {reuse_sessions, true} explicitly to restore previous behavior.

Various missing or faulty sanity checks added and TLS alerts adjusted to comply with RFC MUST requirements, including: signature algorithm validation for intermediate certificates, TLS-1.3 session_id echo, pre_shared_key extension ordering, and renegotiation_info enforcement.

Hardened and improved CRL support. Introduces new option allowed_hosts for the optional CRL HTTP fetching feature to restrict which hosts may be contacted. Internal/loopback IPs are now blocked by default (SSRF protection).

TLS-1.3 client ticket handling is more robust (locked tickets are released on client crash). Server TLS-1.3 ticket handling and anti-replay Bloom filter performance are optimized.

DTLS duplicate ChangeCipherSpec handling simplified, fixing potential state machine confusion (GH-11075).

Process state formatting no longer leaks secrets in crash logs.

Full runtime dependencies of ssl-11.7.5

crypto-5.8, erts-16.0, inets-5.10.7, kernel-10.3, public_key-1.21.1, runtime_tools-1.15.1, stdlib-7.0

The stdlib-8.0.4 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20296

Related Id(s):

GH-11380, PR-11464

Fixed a bug in unicode_util:gc/1 where the grapheme cluster segmentation of $\r (not followed by $\n) would decompose binary continuations into mixed chardata. This caused string:trim/3 (and string:chomp/1) to return incorrect results or crash when trimming strings containing binaries followed by another list element.

OTP-20301

Related Id(s):

ERIERL-1345, PR-11470

record_info/2 will now mark tuple records as used.

OTP-20344

Related Id(s):

PR-11538

uri_string:parse/1 now rejects URIs with an unreasonably long port component (more than 5 digits) instead of attempting to convert an arbitrarily large digit string to an integer.

Full runtime dependencies of stdlib-8.0.4

compiler-5.0, crypto-4.5, erts-16.0.3, kernel-11.0, sasl-3.0, syntax_tools-3.2.1

The tools-4.2.2 application can be applied independently of other applications on a full OTP 29 installation.

OTP-20302

Related Id(s):

PR-11481

tools: fixes tprof not stopping tracing

A call to tprof:enable_trace(new|existing) starts tracing processes. To stop it, one calls tprof:disable_trace(new|existing). However, the guard to stop tracing was matching on new_processes | existing_processes. The return happens to say 0 processes are traced now, but the tracing did not stop. This issue has been fixed.

Full runtime dependencies of tools-4.2.2

compiler-8.5, crypto-5.9, erts-15.0, kernel-10.0, public_key-1.21, runtime_tools-2.1, stdlib-6.0

Andrew Bennett, ausimian, Laurynas Četyrkinas, ruslandoga, Thomas Cioppettini