Edit ChangeLog entry
Signed-off-by: Elena Uziunaite <elena.uziunaite@arm.com>
diff --git a/ChangeLog.d/fix_reporting_of_key_usage_issues.txt b/ChangeLog.d/fix_reporting_of_key_usage_issues.txt
index 12f1bb3..75fbb6c 100644
--- a/ChangeLog.d/fix_reporting_of_key_usage_issues.txt
+++ b/ChangeLog.d/fix_reporting_of_key_usage_issues.txt
@@ -1,4 +1,11 @@
-Bugfix
- * Fix the failure to correctly update verification flags when
- checking the (ext)KeyUsage extension.
- Resolves #1260
+Security
+ * With TLS 1.3, when a server enables optional authentication of the
+ client, if the client-provided certificate does not have appropriate values
+ in if keyUsage or extKeyUsage extensions, then the return value of
+ mbedtls_ssl_get_verify_result() would incorrectly have the
+ MBEDTLS_X509_BADCERT_KEY_USAGE and MBEDTLS_X509_BADCERT_KEY_USAGE bits
+ clear. As a result, an attacker that had a certificate valid for uses other
+ than TLS client authentication could be able to use it for TLS client
+ authentication anyway. Only TLS 1.3 servers were affected, and only with
+ optional authentication (required would abort the handshake with a fatal
+ alert).