From 134f17d526a5d0a9fbd66adf85e53df8a764a2ff Mon Sep 17 00:00:00 2001 From: Bernd Edlinger Date: Mon, 3 Nov 2025 14:00:15 +0100 Subject: [PATCH] Document CVE-2021-4160 This was fixed in openssl 3.0.1 by #17258 and assigned CVE-2021-4160 but unfortunately forgotten to mention in the CHANGES and/or NEWS. Reviewed-by: Paul Yang Reviewed-by: Dmitry Belyavskiy Reviewed-by: Tom Cosgrove Reviewed-by: Tomas Mraz (Merged from https://github.com/openssl/openssl/pull/29051) --- CHANGES.md | 18 ++++++++++++++++++ NEWS.md | 2 ++ 2 files changed, 20 insertions(+) diff --git a/CHANGES.md b/CHANGES.md index a5cfe309845..1869124ef59 100644 --- a/CHANGES.md +++ b/CHANGES.md @@ -2606,6 +2606,24 @@ breaking changes, and mappings for the large list of deprecated functions. ### Changes between 3.0.0 and 3.0.1 [14 Dec 2021] + * Fixed carry bug in BN_mod_exp which may produce incorrect results on MIPS + squaring procedure. Many EC algorithms are affected, including some of the + TLS 1.3 default curves. Impact was not analyzed in detail, because the + pre-requisites for attack are considered unlikely and include reusing + private keys. Analysis suggests that attacks against RSA and DSA as a result + of this defect would be very difficult to perform and are not believed + likely. Attacks against DH are considered just feasible (although very + difficult) because most of the work necessary to deduce information about + a private key may be performed offline. + The amount of resources required for such an attack would be significant. + However, for an attack on TLS to be meaningful, the server would have + to share the DH private key among multiple clients, which is no longer + an option since CVE-2016-0701. + The issue only affects OpenSSL on MIPS platforms. + ([CVE-2021-4160]) + + *Bernd Edlinger* + * Fixed invalid handling of X509_verify_cert() internal errors in libssl Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server. That function may return a diff --git a/NEWS.md b/NEWS.md index 307ef52d80d..10b4d24e07a 100644 --- a/NEWS.md +++ b/NEWS.md @@ -622,6 +622,8 @@ OpenSSL 3.0 ### Major changes between OpenSSL 3.0.0 and OpenSSL 3.0.1 [14 Dec 2021] + * Fixed carry bug in BN_mod_exp which may produce incorrect results on MIPS + ([CVE-2021-4160]) * Fixed invalid handling of X509_verify_cert() internal errors in libssl ([CVE-2021-4044]) * Allow fetching an operation from the provider that owns an unexportable key -- 2.47.3