CVE-2026-104827

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

Published Oct 15, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
react/http is an event-driven, streaming HTTP client and server implementation for ReactPHP. From 1.0.0 until 1.11.1, React\Http\Browser uses ClientRequestStream::handleData() to append response-header bytes to an internal buffer without enforcing a size limit. A remote server can send a valid status line and partial header, withhold the \r\n\r\n or \n\n header terminator, and continue streaming data so the buffer grows for the life of the connection. Applications that fetch attacker-controlled or attacker-influenced URLs, including URLs reached through redirects, can exhaust PHP memory_limit and crash the event-loop or worker process. Confidentiality and integrity are unaffected. This issue is fixed in version 1.11.1.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-g4f2-2pf3-2pwj react/http: Unbounded HTTP Client Response Header Buffering Leads to Memory Exhaustion DoS
History
Type Values Removed Values Added
First Time appeared Reactphp
Reactphp http
Vendors & Products Reactphp
Reactphp http
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description react/http is an event-driven, streaming HTTP client and server implementation for ReactPHP. From 1.0.0 until 1.11.1, React\Http\Browser uses ClientRequestStream::handleData() to append response-header bytes to an internal buffer without enforcing a size limit. A remote server can send a valid status line and partial header, withhold the \r\n\r\n or \n\n header terminator, and continue streaming data so the buffer grows for the life of the connection. Applications that fetch attacker-controlled or attacker-influenced URLs, including URLs reached through redirects, can exhaust PHP memory_limit and crash the event-loop or worker process. Confidentiality and integrity are unaffected. This issue is fixed in version 1.11.1.
Title react/http: Unbounded HTTP Client Response Header Buffering Leads to Memory Exhaustion DoS
Weaknesses CWE-770
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 16, 2026, 5:11 PM
Reserved
Oct 2, 2026, 2:17 PM
Status
Deferred
Published
Oct 15, 2026, 7:17 PM
Modified
Oct 16, 2026, 8:04 PM