[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
react/http	^1.9.0 → ^1.11.1

---

react/http: A malformed HTTP chunked body can lead to a denial-of-service and peg the CPU

CVE-2026-84997 / GHSA-x424-64qh-5j54

More information

Details

Summary

A malformed HTTP message using Transfer-Encoding: chunked can drive React\Http\Io\ChunkedDecoder into an infinite loop, pegging a CPU core and freezing the event loop. Because ReactPHP is single-threaded, one such message stalls the entire process for every client until it is killed.

Both directions are affected. ChunkedDecoder decodes chunked request bodies for React\Http\HttpServer and chunked response bodies for React\Http\Browser, so a server can be attacked by a malicious client and a client can be attacked by a malicious or compromised server.

Details

ChunkedDecoder::handleData() loops while ($this->buffer !== '') and relies on the buffer shrinking each iteration. Two states leave the buffer unchanged while the loop condition stays true.

Terminal-chunk trailer. After the terminating 0 chunk, any remaining buffer is treated as trailer data to skip:

} elseif ($this->chunkSize === 0) {
    $this->buffer = (string)\substr($this->buffer, $positionCrlf);
}

When the trailer holds no CRLF yet, strpos() returns false, PHP coerces that to 0 in substr(), and the buffer is never advanced. Neither the error guard (which requires a non-zero chunk size) nor the wait guard (which requires fewer than two bytes remaining) can fire, so the loop re-enters with identical state.

Off-by-one after a completed chunk. Once a non-terminal chunk has been fully transferred, the "chunk does not end with a CRLF" error guard requires strlen($this->buffer) > 2 while the wait guard requires < 2. Exactly two non-CRLF bytes slip past both, and because the chunk is already complete nothing is consumed on the next iteration.

PoC

Run the example server from the reactphp/reactphp README and send a malformed request. Note the missing trailing \r\n:

POST / HTTP/1.1\r\nHost: x\r\nTransfer-Encoding: chunked\r\n\r\n0\r\nab

The PHP process pegs at 100% CPU and stops answering legitimate requests. A body of 1\r\nAAB triggers the second state.

The client side is reachable the same way: a Browser request to a server that answers with Transfer-Encoding: chunked and either malformed body shape hangs the client process.

Impact

Denial of service. The affected process stops responding entirely and has to be killed.

Servers behind a reverse proxy that parses and re-frames HTTP, such as a typical nginx setup, are not affected on the server side, because the proxy normalises the request before it reaches PHP. That mitigation does not extend to the client side: outbound requests made with Browser reach the remote server directly, so an application fetching attacker-influenced URLs is affected regardless of what sits in front of it.

Severity

• CVSS Score: 7.5 / 10 (High)
• Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

• https://github.com/reactphp/http/security/advisories/GHSA-x424-64qh-5j54
• https://nvd.nist.gov/vuln/detail/CVE-2026-84997
• https://github.com/reactphp/http/commit/b6d4688790adf3797071fcf88a3fc4225f30486a
• https://github.com/FriendsOfPHP/security-advisories/blob/master/react/http/CVE-2026-84997.yaml
• https://github.com/reactphp/http/releases/tag/v1.11.1
• https://github.com/advisories/GHSA-x424-64qh-5j54

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

---

react/http: Unbounded HTTP Client Response Header Buffering Leads to Memory Exhaustion DoS

CVE-2026-104827 / GHSA-g4f2-2pf3-2pwj

More information

Details

Summary

React\Http\Browser and its lower-level HTTP stack impose no limit on the size of a response's header section while it is being received. ClientRequestStream::handleData() appends every incoming byte to an internal buffer and only scans that buffer for the \r\n\r\n (or \n\n) terminator, without ever checking its length. A remote server that withholds the terminator and keeps streaming can grow the client's memory without bound until PHP's memory_limit is exhausted and the process crashes.

This is an unauthenticated, network-reachable denial of service against any application that uses react/http as a client to fetch untrusted or attacker-influenced URLs, including via redirects.

Details

ClientRequestStream::handleData() is bound directly to the underlying connection's data event, so every byte the peer sends is appended with no size check:

public function handleData($data)
{
    $this->buffer .= $data;

    // buffer until double CRLF (or double LF for compatibility with legacy servers)
    $eom = \strpos($this->buffer, "\r\n\r\n");
    $eomLegacy = \strpos($this->buffer, "\n\n");
    if ($eom !== false || $eomLegacy !== false) {

The only exit from the buffering state is finding the header terminator or a connection close, so until it arrives the buffer grows monotonically for as long as the peer keeps sending.

The codebase already applies this class of limit elsewhere, but not symmetrically. RequestHeaderParser caps incoming request headers when acting as a server, and Transaction::bufferResponse() caps the response body, but only once the header section has already been parsed into a Response. Response header reception was the one stage with no limit at all.

PoC

An HTTP server that sends a valid status line and a partial header, then streams indefinitely without ever terminating the header section:

php -r '$s=stream_socket_server("tcp://127.0.0.1:18080"); $c=stream_socket_accept($s); fread($c,8192); fwrite($c,"HTTP/1.1 200 OK\r\nX-Fill: "); while (true) { fwrite($c, str_repeat("A",1048576)); usleep(10000); }'

A client fetching it, with memory_limit=64M:

$browser = new React\Http\Browser();
$browser->get("http://127.0.0.1:18080/")->then(
    function () { echo "ok\n"; },
    function ($e) { echo get_class($e) . ": " . $e->getMessage() . "\n"; }
);

Client memory grows steadily until the process dies with Allowed memory size ... exhausted inside ClientRequestStream::handleData().

Impact

Remotely triggerable, unauthenticated denial of service against any process using Browser to fetch from an attacker-controlled, compromised or otherwise untrusted endpoint, including one reached through a redirect. No user interaction and no special privileges are required. Because there is no upper bound on the header buffer, a single cheap connection can drive memory arbitrarily high and crash the process, taking down whatever event loop or worker it was running. Confidentiality and integrity are unaffected; availability is fully impacted for that process.

Severity

• CVSS Score: 7.5 / 10 (High)
• Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

• https://github.com/reactphp/http/security/advisories/GHSA-g4f2-2pf3-2pwj
• https://github.com/reactphp/http/commit/2558622d0b76227c60c61eac8a61572cb6638e8c
• https://github.com/reactphp/http/releases/tag/v1.11.1
• https://github.com/advisories/GHSA-g4f2-2pf3-2pwj

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

---

Release Notes

reactphp/http (react/http)

v1.11.1

Compare Source

This is a SECURITY release for the 1.x series of ReactPHP's HTTP component.

• Security fix: This release fixes a high severity security issue in ReactPHP's HTTP client and server components
  that affects all versions between v0.6.0 and v1.11.0. All users are encouraged to upgrade immediately.
  (GHSA-x424-64qh-5j54 reported by @​jsifuentes and @​raiFork and fixed by @​jsifuentes and @​clue)

• Security fix: This release fixes a high severity security issue in ReactPHP's HTTP client component
  that affects all versions between v1.0.0 and v1.11.0. All users are encouraged to upgrade immediately.
  (GHSA-g4f2-2pf3-2pwj reported by @​EQSTLab and fixed by @​WyriHaximus)

• Improve test suite PHP 8.4 and 8.5 compatibility.
  (#​546, #​547 and #​551 by @​WyriHaximus)

v1.11.0

Compare Source

• Feature: Improve PHP 8.4+ support by avoiding implicitly nullable types.
  (#​537 by @​clue)

• Feature: Allow underscore character in Uri host.
  (#​524 by @​lulhum)

• Improve test suite to fix expected error code when ext-sockets is not enabled.
  (#​539 by @​WyriHaximus)

---

Configuration

📅 Schedule: (in timezone UTC)

• Branch creation
  • At any time (no schedule defined)
• Automerge
  • At any time (no schedule defined)

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, check this box

---

This PR was generated by Mend Renovate. View the repository job log.