CVE-2019-1543

Source
Severity Low
Remote Yes
Type Information disclosure
Description
An issue has been found in OpenSSL <= 1.1.1b, where an application using ChaCha20-Poly1305 could set a non-default nonce length to be longer than 12 bytes and then mistakenly reuse a nonce.
ChaCha20-Poly1305 is an AEAD cipher, and requires a unique nonce input for every encryption operation. RFC 7539 specifies that the nonce value (IV) should be 96 bits (12 bytes). OpenSSL allows a variable nonce length and front pads the nonce with 0 bytes if it is less than 12 bytes. However it also incorrectly allows a nonce to be set of up to 16 bytes. In this case only the last 12 bytes are significant and any additional leading bytes are ignored.
Group Package Affected Fixed Severity Status Ticket
AVG-920 lib32-openssl 1:1.1.1.b-1 1:1.1.1.c-1 Low Fixed
AVG-919 openssl 1.1.1.b-1 1.1.1.c-1 Low Fixed
Date Advisory Group Package Severity Description
11 Jun 2019 ASA-201906-7 AVG-919 openssl Low information disclosure
11 Jun 2019 ASA-201906-6 AVG-920 lib32-openssl Low information disclosure
References
https://www.openssl.org/news/secadv/20190306.txt
https://github.com/openssl/openssl/commit/f426625b6a