CVE-2026-42772 (GCVE-0-2026-42772)
Vulnerability from cvelistv5
Published
2026-09-29 15:32
Modified
2026-09-30 20:11
Severity ?
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
Summary
Issue summary: The QUIC stream reassembly algorithm performance deteriorates progressively as packets are arriving out of order. The worst case has a quadratic complexity proportional to the number of stream frames kept in the buffer for the received stream data. Impact summary: A remote QUIC peer that completes the handshake can create a connection-scoped CPU pressure and potentially a Denial of Service using compliant STREAM frames inside the advertised receive window, with low attacker bandwidth. CWE: CWE-407: Inefficient Algorithmic Complexity Description: OpenSSL manages received QUIC stream fragments using a doubly-linked list. While it optimizes for append operations (at the end of the list), it falls back to a head-to-tail linear search for any fragment that does not immediately follow the current `tail`. By manipulating the sequence of offsets, an attacker can force the server to perform O(n^2) operations, consuming excessive CPU time for the QUIC process. FIPS impact: no The FIPS module is not affected as the QUIC implementation is outside of the OpenSSL FIPS module boundary.
References
Impacted products
Vendor Product Version
OpenSSL OpenSSL Version: 4.0.0   ≤
Version: 3.6.0   ≤
Version: 3.5.0   ≤
Version: 3.4.0   ≤
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