The version of rsyslog installed on the remote host is prior to 8.24.0-52. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2020-1447 advisory.

    An issue was discovered in Rsyslog v8.1908.0. contrib/pmaixforwardedfrom/pmaixforwardedfrom.c has a heap     overflow in the parser for AIX log messages. The parser tries to locate a log message delimiter (in this     case, a space or a colon) but fails to account for strings that do not satisfy this constraint. If the     string does not match, then the variable lenMsg will reach the value zero and will skip the sanity check     that detects invalid log messages. The message will then be considered valid, and the parser will eat up     the nonexistent colon delimiter. In doing so, it will decrement lenMsg, a signed integer, whose value was     zero and now becomes minus one. The following step in the parser is to shift left the contents of the     message. To do this, it will call memmove with the right pointers to the target and destination strings,     but the lenMsg will now be interpreted as a huge value, causing a heap overflow. (CVE-2019-17041)

    An issue was discovered in Rsyslog v8.1908.0. contrib/pmcisconames/pmcisconames.c has a heap overflow in     the parser for Cisco log messages. The parser tries to locate a log message delimiter (in this case, a     space or a colon), but fails to account for strings that do not satisfy this constraint. If the string     does not match, then the variable lenMsg will reach the value zero and will skip the sanity check that     detects invalid log messages. The message will then be considered valid, and the parser will eat up the     nonexistent colon delimiter. In doing so, it will decrement lenMsg, a signed integer, whose value was zero     and now becomes minus one. The following step in the parser is to shift left the contents of the message.
    To do this, it will call memmove with the right pointers to the target and destination strings, but the     lenMsg will now be interpreted as a huge value, causing a heap overflow. (CVE-2019-17042)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Detections

Analytics

Amazon Linux 2 : rsyslog (ALAS-2020-1447)

critical Nessus Plugin ID 138049

Version 1.4