Skip to main content

NULL Pointer Dereference

CVE-2020-1967

Severity High
Score 7.5/10

Summary

Server or client applications that call the "SSL_check_chain()" function during or after a TLS 1.3 handshake may crash due to a NULL Pointer Dereference as a result of incorrect handling of the "signature_algorithms_cert" TLS extension. The crash occurs if an invalid or unrecognized signature algorithm is received from the peer. This could be exploited by a malicious peer in a Denial of Service attack. OpenSSL version 1.1.1d, 1.1.1e, and 1.1.1f are affected by this issue.

  • LOW
  • NETWORK
  • NONE
  • UNCHANGED
  • NONE
  • NONE
  • NONE
  • HIGH

CWE-476 - NULL Pointer Dereference

A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.

Advisory Timeline

  • Published