Resource exhaustion in Reactphp HTTP
CVE-2026-104827
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.
Published .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Reactphp HTTP — versions >= 1.0.0, < 1.11.1
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-104827?
- CVE-2026-104827 is a high-severity vulnerability in Reactphp HTTP, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-10-15.
- How severe is CVE-2026-104827?
- High severity. CVSS v3 base score is 7.5 out of 10.