CVE-2024-21652

An attacker can exploit a chain of vulnerabilities, including a Denial of Service (DoS) flaw and in-memory data storage weakness, to effectively bypass the application's brute force login protection. This makes the application susceptible to brute force attacks, compromising the security of all user accounts.

Details

The issue arises from two main vulnerabilities:

1. The application crashes due to a previously described DoS vulnerability caused by unsafe array modifications in a multi-threaded environment.
2. The application saves the data of failed login attempts in-memory, without persistent storage. When the application crashes and restarts, this data is lost, resetting the brute force protections.

// LoginAttempts is a timestamped counter for failed login attempts

type LoginAttempts struct {  
// Time of the last failed login LastFailed time.Time `json:"lastFailed"` // Number of consecutive login failures FailCount int `json:"failCount"`

}

By chaining these vulnerabilities, an attacker can circumvent the limitations placed on the number of login attempts.

PoC

1. Run the provided PoC script.
2. Observe that the script makes 6 login attempts, one more than the set limit of 5 failed attempts.
3. This is made possible because the script triggers a server restart via the DoS vulnerability after 5 failed attempts, thus resetting the counter for failed login attempts.

This is a critical security vulnerability that allows attackers to bypass the brute force login protection mechanism. Not only can they crash the service affecting all users, but they can also make unlimited login attempts, increasing the risk of account compromise.

CVE-2024-21652 has a CVSS score of 9.8 (Critical). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.8.13, 2.9.9, 2.10.4); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2024-21652? CVE-2024-21652 is a critical-severity security vulnerability in github.com/argoproj/argo-cd/v2 (go), affecting versions < 2.8.13. It is fixed in 2.8.13, 2.9.9, 2.10.4.
2. How severe is CVE-2024-21652? CVE-2024-21652 has a CVSS score of 9.8 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of github.com/argoproj/argo-cd/v2 are affected by CVE-2024-21652? github.com/argoproj/argo-cd/v2 (go) versions < 2.8.13 is affected.
4. Is there a fix for CVE-2024-21652? Yes. CVE-2024-21652 is fixed in 2.8.13, 2.9.9, 2.10.4. Upgrade to this version or later.
5. Is CVE-2024-21652 exploitable, and should I be worried? Whether CVE-2024-21652 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2024-21652 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2024-21652?
   • Upgrade github.com/argoproj/argo-cd/v2 to 2.8.13 or later
   • Upgrade github.com/argoproj/argo-cd/v2 to 2.9.9 or later
   • Upgrade github.com/argoproj/argo-cd/v2 to 2.10.4 or later