Vulnerability · Published Jul 19, 2023 · Assigned by openssl

CVE-2023-3446Excessive time spent checking DH keys and parameters

Medium 5.3

In plain English

A medium-severity security flaw in OpenSSL from OpenSSL. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 6.5% (higher than 94% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.3Medium
Exploit odds (30 days)6.5%top 6.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Issue summary: Checking excessively long DH keys or parameters may be very slow. Impact summary: Applications that use the functions DH_check(), DH_check_ex() or EVP_PKEY_param_check() to check a DH key or DH parameters may experience long delays. Where the key or parameters that are being checked have been obtained from an untrusted source this may lead to a Denial of Service. The function DH_check() performs various checks on DH parameters. One of those checks confirms that the modulus ('p' parameter) is not too large. Trying to use a very large modulus is slow and OpenSSL will not normally use a modulus which is over 10,000 bits in length. However the DH_check() function checks numerous aspects of the key or parameters that have been supplied. Some of those checks use the supplied modulus value even if it has already been found to be too large. An application that calls DH_check() and supplies a key or parameters obtained from an untrusted source could be vulernable to a Denial of Service attack. The function DH_check() is itself called by a number of other OpenSSL functions. An application calling any of those other functions may similarly be affected. The other functions affected by this are DH_check_ex() and EVP_PKEY_param_check(). Also vulnerable are the OpenSSL dhparam and pkeyparam command line applications when using the '-check' option. The OpenSSL SSL/TLS implementation is not affected by this issue. The OpenSSL 3.0 and 3.1 FIPS providers are not affected by this issue.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:8edk2-aarch6420220126gitbb1bba3d77-6.el8_9.3ALSA-2024:0888
AlmaLinux:9edk2-aarch6420231122-6.el9ALSA-2024:2264
AlmaLinux:8edk2-ovmf20220126gitbb1bba3d77-6.el8_9.3ALSA-2024:0888
AlmaLinux:9edk2-ovmf20231122-6.el9ALSA-2024:2264
AlmaLinux:9edk2-tools20231122-6.el9ALSA-2024:2264
AlmaLinux:9edk2-tools-doc20231122-6.el9ALSA-2024:2264
AlmaLinux:8openssl1:1.1.1k-12.el8_9ALSA-2023:7877
AlmaLinux:9openssl1:3.0.7-27.el9ALSA-2024:2447
AlmaLinux:8openssl-devel1:1.1.1k-12.el8_9ALSA-2023:7877
AlmaLinux:9openssl-devel1:3.0.7-27.el9ALSA-2024:2447
AlmaLinux:8openssl-libs1:1.1.1k-12.el8_9ALSA-2023:7877
AlmaLinux:9openssl-libs1:3.0.7-27.el9ALSA-2024:2447
AlmaLinux:8openssl-perl1:1.1.1k-12.el8_9ALSA-2023:7877
AlmaLinux:9openssl-perl1:3.0.7-27.el9ALSA-2024:2447
Alpine:v3.20openssl3.1.1-r3ALPINE-CVE-2023-3446
Alpine:v3.21openssl3.1.1-r3ALPINE-CVE-2023-3446
Alpine:v3.22openssl3.1.1-r3ALPINE-CVE-2023-3446
Alpine:v3.23openssl3.1.1-r3ALPINE-CVE-2023-3446
Alpine:v3.24openssl3.1.1-r3ALPINE-CVE-2023-3446
Debian:12openssl3.0.10-1~deb12u1DEBIAN-CVE-2023-3446
Debian:13openssl3.0.10-1DEBIAN-CVE-2023-3446
Debian:14openssl3.0.10-1DEBIAN-CVE-2023-3446
Rocky Linux:9edk20:20231122-6.el9RLSA-2024:2264
Rocky Linux:8openssl1:1.1.1k-12.el8_9RLSA-2023:7877
Ubuntu:22.04:LTSedk22022.02-3ubuntu0.22.04.4USN-7894-1
Ubuntu:22.04:LTSedk22022.02-3ubuntu0.22.04.4UBUNTU-CVE-2023-3446
Ubuntu:24.04:LTSedk22024.02-2ubuntu0.6USN-7894-1
Ubuntu:24.04:LTSedk22024.02-2ubuntu0.6UBUNTU-CVE-2023-3446
Ubuntu:22.04:LTSopenssl3.0.2-0ubuntu1.12USN-6450-1
Ubuntu:22.04:LTSopenssl3.0.2-0ubuntu1.12UBUNTU-CVE-2023-3446

Affected products (as reported)

VendorProductVersions
OpenSSL OpenSSL 3.1.0 – before 3.1.23.0.0 – before 3.0.101.1.1 – before 1.1.1v1.0.2 – before 1.0.2zi

Weakness: CWE-606 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References