TLS 1.3 CompressedCertificate excessive memory allocation
ディストリビューション別の修正状況
各ディストリビューションが公開している、この CVE の修正パッケージ
- Alpine Linux ALPINE-CVE-2025-66199 openssl 修正版: 3.3.6-r0
- Debian DEBIAN-CVE-2025-66199 openssl 修正版: 3.5.4-1~deb13u2
- Ubuntu UBUNTU-CVE-2025-66199 nodejs
原文の説明 取得元が公開している説明をそのまま載せています (多くは英語)。
Issue summary: A TLS 1.3 connection using certificate compression can be
forced to allocate a large buffer before decompression without checking
against the configured certificate size limit.
Impact summary: An attacker can cause per-connection memory allocations of
up to approximately 22 MiB and extra CPU work, potentially leading to
service degradation or resource exhaustion (Denial of Service).
In affected configurations, the peer-supplied uncompressed certificate
length from a CompressedCertificate message is used to grow a heap buffer
prior to decompression. This length is not bounded by the max_cert_list
setting, which otherwise constrains certificate message sizes. An attacker
can exploit this to cause large per-connection allocations followed by
handshake failure. No memory corruption or information disclosure occurs.
This issue only affects builds where TLS 1.3 certificate compression is
compiled in (i.e., not OPENSSL_NO_COMP_ALG) and at least one compression
algorithm (brotli, zlib, or zstd) is available, and where the compression
extension is negotiated. Both clients receiving a server CompressedCertificate
and servers in mutual TLS scenarios receiving a client CompressedCertificate
are affected. Servers that do not request client certificates are not
vulnerable to client-initiated attacks.
Users can mitigate this issue by setting SSL_OP_NO_RX_CERTIFICATE_COMPRESSION
to disable receiving compressed certificates.
The FIPS modules in 3.6, 3.5, 3.4 and 3.3 are no…
参照URL
- advisory github.com
- advisory nvd.nist.gov
- advisory openssl-library.org
- patch github.com
- patch github.com
- patch github.com
- patch github.com