CVE-2023-29409

Published: 2 August 2023

Extremely large RSA keys in certificate chains can cause a client/server to expend significant CPU time verifying signatures. With fix, the size of RSA keys transmitted during handshakes is restricted to <= 8192 bits. Based on a survey of publicly trusted RSA keys, there are currently only three certificates in circulation with keys larger than this, and all three appear to be test certificates that are not actively deployed. It is possible there are larger keys in use in private PKIs, but we target the web PKI, so causing breakage here in the interests of increasing the default safety of users of crypto/tls seems reasonable.

Priority

Cvss 3 Severity Score

5.3

Score breakdown

Status

Package	Release	Status
golang-1.19 Launchpad, Ubuntu, Debian	bionic	Ignored (end of standard support)
	focal	Does not exist
	jammy	Does not exist
	lunar	Ignored (end of life, was needs-triage)
	mantic	Does not exist
	noble	Does not exist
	trusty	Ignored (end of standard support)
	upstream	Released (1.19.12-1)
	xenial	Ignored (end of standard support)
golang-1.20 Launchpad, Ubuntu, Debian	bionic	Ignored (end of standard support)
	focal	Needs triage
	jammy	Needs triage
	lunar	Ignored (end of life, was needs-triage)
	mantic	Needs triage
	noble	Does not exist
	trusty	Ignored (end of standard support)
	upstream	Released (1.20.7-1)
	xenial	Ignored (end of standard support)

Severity score breakdown

Parameter	Value
Base score	5.3
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

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