CVE-2023-29409

Large RSA keys can cause high CPU usage in crypto/tls

State
Published
Severity
Not scored
Published
Aug 2, 2023
Updated
Feb 13, 2025
Reserved
Apr 5, 2023

Read the record on cve.org

Description

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.

Scores

The record has no CVSS score.

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
crypto/tlsGo standard library
  • before 1.19.12Affected
  • 1.20.0-0 to before 1.20.7Affected
  • 1.21.0-0 to before 1.21.0-rc.4Affected

References

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