CVE-2019-17041 Memory corruption in n/a
A heap overflow in Rsyslog's AIX log parser allows attackers to cause denial of service or execute arbitrary code via crafted log messages.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2019-17041?
CVE-2019-17041 is a critical memory corruption vulnerability in Debian Debian Linux, published on 7 Oct 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-787
Which versions are affected by CVE-2019-17041?
It affects 4 products.
Products include Debian Debian Linux, Fedoraproject Fedora, Opensuse Leap, Rsyslog Rsyslog.
How do I fix CVE-2019-17041?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2019-17041 being exploited?
There is no known exploitation of CVE-2019-17041 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as ALPINE-CVE-2019-17041, DEBIAN-CVE-2019-17041, GHSA-wvqp-mg76-5qw7, UBUNTU-CVE-2019-17041.