We use these services and cookies to improve your user experience. You may opt out if you wish, however, this may limit some features on this site.

Please see our statement on Data Privacy.

Crisp.chat (Helpdesk and Chat)

Ok

THREATINT
PUBLISHED

CVE-2023-3724

TLS 1.3 client issue handling malicious server when not including a KSE and PSK extension



AssignerwolfSSL
Reserved2023-07-17
Published2023-07-17
Updated2024-10-29

Description

If a TLS 1.3 client gets neither a PSK (pre shared key) extension nor a KSE (key share extension) when connecting to a malicious server, a default predictable buffer gets used for the IKM (Input Keying Material) value when generating the session master secret. Using a potentially known IKM value when generating the session master secret key compromises the key generated, allowing an eavesdropper to reconstruct it and potentially allowing access to or meddling with message contents in the session. This issue does not affect client validation of connected servers, nor expose private key information, but could result in an insecure TLS 1.3 session when not controlling both sides of the connection. wolfSSL recommends that TLS 1.3 client side users update the version of wolfSSL used.



CRITICAL: 9.1CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Product status

Default status
unaffected

3.14.0
affected

Credits

Johannes from Sectra Communications and Linköping University finder

References

https://github.com/wolfSSL/wolfssl/pull/6412 (github) patch

https://www.wolfssl.com/docs/security-vulnerabilities/ (website)

cve.org CVE-2023-3724

nvd.nist.gov CVE-2023-3724

Download JSON

Share this page
https://cve.threatint.com/CVE/CVE-2023-3724
Subscribe to our newsletter to learn more about our work.