--- title: Research and Insights | Andrei Herasimau description: As a penetration tester, Andrei explores our customers' systems and checks them for vulnerabilities. During his studies at ETH Zurich, he was able to gain knowledge about secure software development, which he now uses in practice. image: https://avantguard.io/hubfs/raw_assets/public/avantguard/images/og-default.png --- [Skip to content](https://avantguard.io/en/blog/author/andrei-herasimau#main) [![avantguard cyber security](https://avantguard.io/hs-fs/hubfs/LogoInverted.png?width=128&height=61&name=LogoInverted.png)](https://avantguard.io/en/) - [Services](https://avantguard.io/en/services) - [About Us](https://avantguard.io/en/about-us) - [Experience](https://avantguard.io/en/experience) - [Career](https://avantguard.io/en/careers) - [Research](https://avantguard.io/en/blog) - [Contact](https://avantguard.io/en/contact) [DE](https://avantguard.io/blog) EN [Request an offer](https://avantguard.io/en/request-an-offer) [DE](https://avantguard.io/blog) EN [Request an offer](https://avantguard.io/en/request-an-offer) Posts by ![](https://avantguard.io/hs-fs/hubfs/AboutUs/C99A8322_blog.png?width=96&height=96&name=C99A8322_blog.png) # Andrei Herasimau As a penetration tester, Andrei explores our customers' systems and checks them for vulnerabilities. During his studies at ETH Zurich, he was able to gain knowledge about secure software development, which he now uses in practice. Search the blog Search - [All](https://avantguard.io/en/blog) - [Offensive](https://avantguard.io/en/blog/tag/offensive) - [Red Team](https://avantguard.io/en/blog/tag/red-team) - [Research](https://avantguard.io/en/blog/tag/research) - [Covenant](https://avantguard.io/en/blog/tag/covenant) - [Bypass](https://avantguard.io/en/blog/tag/bypass) - [AI](https://avantguard.io/en/blog/tag/ai) - [Cleartext Credentials](https://avantguard.io/en/blog/tag/cleartext-credentials) - [Defensive](https://avantguard.io/en/blog/tag/defensive) - [News](https://avantguard.io/en/blog/tag/news) - [Review](https://avantguard.io/en/blog/tag/review) - [AD CS](https://avantguard.io/en/blog/tag/ad-cs) - [Active Directory](https://avantguard.io/en/blog/tag/active-directory) - [Conti](https://avantguard.io/en/blog/tag/conti) - [HTB](https://avantguard.io/en/blog/tag/htb) - [Keepass](https://avantguard.io/en/blog/tag/keepass) - [PingCastle](https://avantguard.io/en/blog/tag/pingcastle) - [PowerShell](https://avantguard.io/en/blog/tag/powershell) - [Pro Labs](https://avantguard.io/en/blog/tag/pro-labs) - [Ransomware](https://avantguard.io/en/blog/tag/ransomware) - [Shares](https://avantguard.io/en/blog/tag/shares) - [Snaffler](https://avantguard.io/en/blog/tag/snaffler) [![](https://avantguard.io/hs-fs/hubfs/Blog/BlueHammerRedSun/bluehammer-1.png?width=800&name=bluehammer-1.png)](https://avantguard.io/en/blog/bluehammer-und-redsun-analysiert) - [Offensive](https://avantguard.io/en/blog/tag/offensive) - [Red Team](https://avantguard.io/en/blog/tag/red-team) - [News](https://avantguard.io/en/blog/tag/news) ### [BlueHammer and RedSun analysed](https://avantguard.io/en/blog/bluehammer-und-redsun-analysiert) This article takes a closer look at two recent vulnerabilities, BlueHammer and RedSun, and explains why they have attracted so much attention. [Andrei Herasimau](https://avantguard.io/en/blog/author/andrei-herasimau) June 9, 2026 15 min read [![](https://avantguard.io/hs-fs/hubfs/Blog/NTLMv1/rainbow_table_structure.png?width=800&name=rainbow_table_structure.png)](https://avantguard.io/en/blog/die-sünden-von-ntlmv1) - [Offensive](https://avantguard.io/en/blog/tag/offensive) - [Red Team](https://avantguard.io/en/blog/tag/red-team) ### [The Sins Of NTLMv1](https://avantguard.io/en/blog/die-sünden-von-ntlmv1) Why NTLMv1 is insecure and two of the most popular attack vectors: brute-force attacks (particularly rainbow table attacks) and relaying attacks. [Andrei Herasimau](https://avantguard.io/en/blog/author/andrei-herasimau) February 3, 2026 13 min read [![](https://avantguard.io/hs-fs/hubfs/Blog/mitre_atlas.png?width=800&name=mitre_atlas.png)](https://avantguard.io/en/blog/penetration-testing-for-ai-applications) - [Research](https://avantguard.io/en/blog/tag/research) - [AI](https://avantguard.io/en/blog/tag/ai) ### [Penetration Testing For AI Applications](https://avantguard.io/en/blog/penetration-testing-for-ai-applications) An insight into the rapidly expanding field of testing AI applications for vulnerabilities from a penetration tester's perspective. [Andrei Herasimau](https://avantguard.io/en/blog/author/andrei-herasimau) December 2, 2024 13 min read ## Wie sicher sind Ihre Systeme wirklich? Erzählen Sie uns von Ihrem Vorhaben. Sie erhalten ein unverbindliches Angebot. [Offerte anfragen](https://avantguard.io/offerte-anfragen) [+41 55 253 30 30](tel:+41552533030) [![avantguard cyber security](https://avantguard.io/hs-fs/hubfs/LogoInverted.png?width=140&height=66&name=LogoInverted.png)](https://avantguard.io/en/) avantguard cyber security AG Neue Jonastrasse 52 8640 Rapperswil-Jona, Switzerland [+41 55 253 30 30](tel:+41552533030) [info@avantguard.io](mailto:info@avantguard.io) ## Company - [Services](https://avantguard.io/en/services) - [About us](https://avantguard.io/en/about-us) - [Experience](https://avantguard.io/en/experience) - [AI at avantguard](https://avantguard.io/en/ai-at-avantguard) - [Careers](https://avantguard.io/en/careers) - [Research](https://avantguard.io/en/blog) - [Contact](https://avantguard.io/en/contact) ## Services - [Penetration Testing](https://avantguard.io/en/penetration-test) - [Red Teaming](https://avantguard.io/en/red-teaming) - [Attack Simulation](https://avantguard.io/en/attack-simulation) - [FINMA-regulated pentesting](https://avantguard.io/en/finma-regulated-pentesting) - [AD Security Improvement](https://avantguard.io/en/ad_improvement) - [mesher](https://avantguard.io/en/mesher) - [All services](https://avantguard.io/en/services) ## Research - [Does Your New Camera Come with a Backdoor?](https://avantguard.io/en/blog/kommt-ihre-neue-kamera-mit-backdoor) - [The Blind Spot Of 802.1X Network Access Control (NAC)](https://avantguard.io/en/blog/die-blinde-stelle-von-802.1x-network-access-control-nac) - [BlueHammer and RedSun analysed](https://avantguard.io/en/blog/bluehammer-und-redsun-analysiert) - [Plaintext in Memory: Revisiting Browser Password Security](https://avantguard.io/en/blog/klartext-im-speicher-neubewertung-der-passwortsicherheit-im-browser) - [All posts](https://avantguard.io/en/blog) © 2026 avantguard cyber security AG - [Privacy policy](https://avantguard.io/en/privacy-policy) - [Deutsch](https://avantguard.io/)