This blog is a smaller part of an article in Bugcrowd’s newest report, Inside the Mind of a CISO. Check out the report for the full article, along with other thought pieces, infographics, and data analyses for CISOs and security leaders.

In the newest edition of Inside the Mind of a CISO, we analyzed hundreds of thousands of vulnerability submission data over the past year of private and public security engagements. In doing this, we identified the top five most commonly reported VRT categories for critical (P1) vulnerabilities.

The top five VRT categories are:

  1. Server security misconfiguration
  2. Server-side injection
  3. Broken access control
  4. Sensitive data exposure
  5. Broken authentication and session management

We asked top hackers to help break down these categories and the potential impact of these vulnerabilities.

Server security misconfiguration

Server security misconfigurations remain one of the most common and dangerous weaknesses in modern environments. Misconfigured authentication, caching, or access controls can turn low-severity issues into critical breaches. Through my own work, I’ve located admin panels left exposed via default credentials, granting unrestricted system access. I’ve also uncovered a low-level rate limiting flaw on cached URLs containing sensitive documents protected by OTP codes. By combining predictable caching behavior with the rate limiting weakness, I was able to bypass the OTP requirement entirely and escalate the issue to a critical vulnerability. These cases show how small oversights can create significant risk when chained together.

Masonhck357

 

Server-side injection

Whenever we type something into a website, a search box, a login form, or even a comment box, it sends that information to a server in the form of parameters and its value to process. Normally, a server should treat our input as plain, harmless text. But with server-side injections, attackers can send specially crafted text, called a payload, that the server will follow as if it were a legitimate command or instruction, considering my input as a part of its own coding.

This could lead to the attacker stealing all of your data, locking you out of your own system, demanding a ransom, or selling your stolen information on the dark web.

Anon Hunter

 

Broken access control

Broken access control vulnerabilities should be a priority for every security team for three main reasons: ease of exploitation, likelihood of exploitation, and compliance requirements. Most of these vulnerabilities are easy to exploit, even for novice attackers. Threat actors are actively targeting these flaws to breach companies and leak data. Standards like the GDPR and HIPAA mandate strong access control. Failure to address these issues can result in significant fines and penalties.

From my experience, these vulnerabilities often leak critical information like PII, healthcare data, confidential system information, and internal documents. They are absolutely necessary to address.

DK999

 

Sensitive data exposure

The potential impact of sensitive data exposure can be a legal, financial, and reputational nightmare. Often, the sensitive data that is exposed—user names, addresses, IDs, and mobile numbers—are just part of an attack, and the attacker is pivoting their way deep into and across your network. By the time you find the breach, attackers have often already been working their way through your network for months. Meanwhile, they’ve already sold the data to the highest bidder, and now you and your organization are being targeted with phishing emails tweaked in just the right way to get you to engage. 

These vulnerabilities are an obvious priority for security teams and CISOs. They must be identified and fixed quickly.

Brig

 

Broken authentication and session management

Broken authentication and session management bugs are common vulnerabilities that often go unnoticed, but they have critical impact on businesses. Even if you invest in a great firewall and EDR and keep a completely clean dashboard, these bugs can run in the background, meaning someone can impersonate a legitimate user account without your security team getting any alerts. 

These can be devastating from a business risk perspective. From a compliance and regulatory perspective, they can trigger GDPR or CCPA penalties because they commonly concern sensitive customer data. There is also a downstream impact. Attackers can chain together these vulnerabilities, leading to more advanced attacks. 

Aituglo