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FOSDEM 2020 videos.

Video recordings from FOSDEM 2020 are now available. The OpenBSD presentations were:

• Giovanni Bechis (giovanni@) - OpenSMTPD over the clouds, the story of an HA setup.
• Florian Obser (florian@) - unwind(8), A privilege-separated, validating DNS recursive nameserver for every laptop.

https://undeadly.org/cgi?action=article;sid=20200211080946

#fosdem #video
SNMP v3 check for OpenBSD systems state monitoring

This script uses SNMPv3 to check memory and swap usage, file system space usage and CPU load average on OpenBSD system. It also shows detailed information about all avaliable file systems, configured NICs, system information about OS and list of running processes.

https://github.com/alexander-naumov/openbsd_snmp3_check

#snmp #monitoring
Running Sagan on OpenBSD 6.6.

Sagan uses a 'Snort like' engine and rules to analyze logs (syslog/event log/snmptrap/netflow/etc).

https://gist.github.com/litew/1e94730ed1b862aa59d4c6b065a0d4a9

#security #sagan
Monitoring OpenBSD with Grafana and Prometheus.

With any deployment of OpenBSD, it is always advisable to have some sort of monitoring enabled... Last week, I ended up moving over to a Grafana dashboard with prometheus as the monitoring system...

https://www.findelabs.com/post/grafana-prometheus-monitoring-openbsd/

#grafana #prometheus #monitoring
Vulnerabilities(?) in OpenBSD's hypervisor.

Three things are wrong:

1) The RO protections are not enforced, so the guest could have data be written to a GPA it can only access as RO.

2) If 'pvclock_ti' crosses a page, its second half could point to an HPA that doesn't belong to the guest. The guest can therefore, to some limited extent, overwrite host kernel memory.

3) The pmap is not locked, so if the GPA gets unmapped and its corresponding HPA recycled, there is a small window where the (new) content of the HPA can get overwritten.

https://marc.info/?l=openbsd-tech&m=158176939604512&w=2

#security
Configure login(1) and sshd(8) for YubiKey on OpenBSD.

https://rgz.ee/openbsd/yubikey.html

#sshd #yubikey
The results are in. About 5 billion fuzz cases, a few 10 hours streams, and we found 6 unique bugs in OpenBSD ctags. All with an absolutely garbage fuzzer. Some were pretty tricky (uninit stack use, global overflows), but vecemu was able to detect em!

https://twitter.com/gamozolabs/status/1229379329248784385

https://gist.github.com/gamozolabs/ac79a6d755e44d71f5bf0659a0848265

#security #ctags #fuzzing
LPE and RCE in OpenSMTPD's default install (CVE-2020-8794).

https://www.openwall.com/lists/oss-security/2020/02/24/5

#opensmtpd #security
Remote root exploits are now publicly available for LPE and RCE in OpenBSD's OpenSMTPD's default install (CVE-2020-8794).

https://www.openwall.com/lists/oss-security/2020/02/26/1

#security #opensmtpd
My machines are hosted in 3 different places. First is at Exoscale, second is Vultr and the third is... my flat. All of them run either OpenBSD on its -current branch, or the latest version of Ubuntu. At this time, that's Ubuntu 19.10. After a couple of years working on OpenBSD ports (i.e. packaging), I believe fresh software is better, security-wise.

https://chown.me/blog/infrastructure-2019.html

#server
Using OpenBSD relayd to Add Security Headers.

I am a huge fan of OpenBSD’s built-in httpd server as it is simple, secure, and quite performant. With the modern push of the large search providers pushing secure websites, it is now important to add security headers to your website or risk having the search results for your website downgraded. Fortunately, it is very easy to do this when you combine httpd with relayd.

https://goblackcat.com/posts/using-openbsd-relayd-to-add-security-headers/

#relayd
Introduction to doas on OpenBSD.

OpenBSD's alternative to sudo is doas, although it does not work the same way as sudo and requires some configuration...

https://www.vultr.com/docs/introduction-to-doas-on-openbsd

#doas
Fullstack mailserver based on OpenSMTPD for OpenBSD using ansible

https://github.com/AnsiMail/AnsiMail

#ansible #opensmtpd