SARA / Free Tools / CVE / CVE-2023-29409

CVE-2023-29409 — Extremely large RSA keys in certificate chains can cause a client/server to expe

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 c

CVSS
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EPSS
0.11% (top 70.10%)
CWE
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Published
2023-08-02T19:47:23.829Z
Last modified
2025-02-13T16:49:16.368Z
CVSS vector
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01What is this vulnerability?

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…

02Affected products

VendorProductVersions
Go standard librarycrypto/tls0, 1.20.0-0, 1.21.0-0

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

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