PentesterLab

Don’t just learn tools and payloads. Learn why vulnerabilities exist. Hands-on web hacking, security code review, and real-world CVE labs.

[PentesterLab @PentesterLab]

💥🐹 4 new Go Code Review Labs just dropped! 🐹💥

Read the code, peek at the diff, find the bug.

Sharpen your skills: https://t.co/0Y56bXk2oa

[PentesterLab @PentesterLab]

WUBBA LUBBA DUB DUB!

Can you guess the vulnerability? 🥒🐍

Wrong answers encouraged.

[PentesterLab @PentesterLab]

Two new on-demand courses, fully recorded and ready:

🔎 Web Security Code Review

🐹 Secure Coding for Go Developers, beyond the OWASP Top 10

Learn at your own pace. Launch discounts available now:

https://t.co/eqlUSylVXD

[Louis Nyffenegger @snyff]

"She's a 4, but she's the private key of an intermediate certificate authority..."

[PentesterLab @PentesterLab]

In 2008, Debian disclosed that a change intended to silence Valgrind warnings had broken OpenSSL's random number generator.

The change removed code that mixed entropy into its internal state, leaving the process ID as the only meaningful source of variability. Attackers could precompute the possible keys instead of breaking the cryptography.

In 2026, eight of eMudhra's intermediate CA private keys turned out to be:

4, 56, 66, 115, 155, 156, 230, 237.

[PentesterLab @PentesterLab]

@jundybaba Congrats!

[ju4dy @jundybaba]

I just completed @Pentesterlab's HTTP Badge!!!
lfg

[PentesterLab @PentesterLab]

Assumptions are at the root of so many security issues. When testing an application or reviewing code, always ask yourself: "What assumptions did the developer make? What assumptions am I making when I say this is secure?"

Maybe you're assuming that an input has already been validated, that a route requires authentication, or that a framework handles a security check for you.

Each of those assumptions deserves to be verified.

Questioning the developer's assumptions is part of the job, but questioning your own is just as important.

[PentesterLab @PentesterLab]

@coffeefiend52 Congrats! Keep it up!

[coffeefiend52 @coffeefiend52]

I just completed @Pentesterlab's Web Fundamentals!

[PentesterLab @PentesterLab]

@coffeefiend52 Congrats! Keep it up 🚀

[coffeefiend52 @coffeefiend52]

I just completed @Pentesterlab's API Badge!!!

[PentesterLab @PentesterLab]

With moderation...

[PentesterLab @PentesterLab]

@R1th1k_Sarv3sh That's the spirit 🚀🚀🚀

[PentesterLab @PentesterLab]

Getting a CVE is easy when you're the one writing the vulnerabilities.

Just make sure you clarify what you mean by "responsible for 30 CVEs" on your resume... 😉

[PentesterLab @PentesterLab]

@_alekum_ A bike and 2 DGX Sparks 😉

[PentesterLab @PentesterLab]

Put some Spark in your relationship. 💍

[PentesterLab @PentesterLab]

@_alekum_ Get your priorities right!

[PentesterLab @PentesterLab]

@_alekum_

[PentesterLab @PentesterLab]

@raftomas Can you put a price on love?