CVE-2026-42772
N/A
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.
Affected Software
| Vendor | Product | Version Range | Status |
|---|---|---|---|
| OpenSSL | OpenSSL | 4.0.0 < 4.0.3 | affected |
| OpenSSL | OpenSSL | 3.6.0 < 3.6.5 | affected |
| OpenSSL | OpenSSL | 3.5.0 < 3.5.9 | affected |
| OpenSSL | OpenSSL | 3.4.0 < 3.4.8 | affected |
Weaknesses
- CWE-407: CWE-407 Inefficient Algorithmic Complexity
References
- https://openssl-library.org/news/secadv/20260929.txt
- https://github.com/openssl/openssl/commit/f42ae513bbda513b3c121d54834040ee4a0eae1a
- https://github.com/openssl/openssl/commit/32d0ed8afe1b8c3e7ece725b44663da3d7087a09
- https://github.com/openssl/openssl/commit/ca8402e273af4de5b3f04fa61a0f0c02ce3ae20e
- https://github.com/openssl/openssl/commit/eb2becc0a4baea7f3050a247834d0e5c2ebe1773
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