CVE-2023-3446

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.

Why is this CVE low priority?

Upstream openssl developers have rated this issue as being low severity

Learn more about Ubuntu priority

Status

Show unmaintained releases

Package	Ubuntu Release	Status
edk2	24.04 LTS noble	Vulnerable
	23.10 mantic	Ignored
	23.04 lunar	Ignored
	22.10 kinetic	Ignored
	22.04 LTS jammy	Vulnerable
	20.04 LTS focal	Vulnerable
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation
	14.04 LTS trusty	Ignored
nodejs	24.04 LTS noble	Not affected
	23.10 mantic	Not affected
	23.04 lunar	Not affected
	22.10 kinetic	Not affected
	22.04 LTS jammy	Vulnerable
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation
	14.04 LTS trusty	Not affected
openssl	24.04 LTS noble	Not affected
	23.10 mantic	Not affected
	23.04 lunar	Fixed 3.0.8-1ubuntu1.4
	22.10 kinetic	Ignored
	22.04 LTS jammy	Fixed 3.0.2-0ubuntu1.12
	20.04 LTS focal	Fixed 1.1.1f-1ubuntu2.20
	18.04 LTS bionic	Fixed 1.1.1-1ubuntu2.1~18.04.23+esm3 Ubuntu Pro
	16.04 LTS xenial	Fixed 1.0.2g-1ubuntu4.20+esm10 Ubuntu Pro
	14.04 LTS trusty	Fixed 1.0.1f-1ubuntu2.27+esm10 Ubuntu Pro
openssl1.0	24.04 LTS noble	Not in release
	23.10 mantic	Not in release
	23.04 lunar	Not in release
	22.10 kinetic	Not in release
	22.04 LTS jammy	Not in release
	20.04 LTS focal	Not in release
	18.04 LTS bionic	Fixed 1.0.2n-1ubuntu5.13+esm1 Ubuntu Pro
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release

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Severity score breakdown

Parameter	Value
Base score	5.3 · Medium
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	Low
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References

Related Ubuntu Security Notices (USN)

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