p PatchFirst

CVE-2023-29409

CVE-2023-29409 · Large RSA keys can cause high CPU usage in crypto/tls

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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.

CVSS 5.3 · Medium · EPSS 1.6% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • crypto/tls

    Versions
    • ≥ 0, < 1.19.12: Affected (semver)
    • ≥ 1.20.0-0, < 1.20.7: Affected (semver)
    • ≥ 1.21.0-0, < 1.21.0-rc.4: Affected (semver)

    Update to 1.19.12; Update to 1.20.7; Update to 1.21.0-rc.4

  • golang-1.19 Debian:12

    Versions
    • 1.19.10-1
    • 1.19.10-2
    • 1.19.11-1
    • 1.19.12-1
    • 1.19.12-2
    • 1.19.12-2~bpo11+1
    • 1.19.12-2~bpo12+1
    • 1.19.13-1
    • 1.19.13-1~bpo11+1
    • 1.19.13-1~bpo12+1
    • 1.19.8-2
    • 1.19.9-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • golang-1.20 Ubuntu:20.04:LTS

    Versions
    • 1.20.3-1ubuntu0.1~20.04
    • 1.20.3-1ubuntu0.1~20.04.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • golang-1.20 Ubuntu:22.04:LTS

    Versions
    • 1.20.3-1ubuntu0.1~22.04
    • 1.20.3-1ubuntu0.1~22.04.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

Check your server →