When it comes to software vulnerabilities, some security warnings appear and then quietly disappear. One such example is CVE-2021-33152. If you try to look it up, you’ll find it was marked as REJECTED—but what does that even mean, and why does it matter? In this long read, let’s break down the case of CVE-2021-33152, using simple language, code snippets, and all the important links.
What is CVE-2021-33152? ###
CVE-2021-33152 was reserved for a vulnerability report but was never actually used to document an issue. Here’s the official record:
> Reason: This candidate was withdrawn by its requester. This CVE ID was not used. No action is required or recommended regarding this CVE ID.
> References: NVD Entry
What Does "REJECTED" Mean in CVEs? ##
The Common Vulnerabilities and Exposures (CVE) database assigns unique identifiers to security vulnerabilities. Sometimes, a CVE ID is set aside for a reported problem, but later it's decided that there was either no real issue, a duplicate exists, or a mistake was made. In these cases, the CVE gets a REJECTED status.
> REJECTED REASON: This is unused.
It means that this entry will not describe any actual software problem.
Common reasons for "Unused" CVEs
* The reported bug was found not to be a security issue.
* The CVE was reserved in error.
* The vulnerability was a duplicate of another CVE.
* The issue was fixed before publication and is not exploitable.
In the case of CVE-2021-33152, the only information provided is that it was unused.
How Does This Affect Users? ##
The good news: You don’t need to worry about CVE-2021-33152. There is no known exploit, no patch, and no risk—because there is no actual vulnerability behind this CVE number.
What Would an Exploit Look Like (If It Had Existed)? ##
To illustrate, let’s think about a generic case where a CVE *wasn’t* rejected. For example, a buffer overflow in C might look like:
#include <stdio.h>
#include <string.h>
void vulnerable_function(char *input) {
char buffer[100];
// Dangerous: no bounds checking!
strcpy(buffer, input);
}
int main(int argc, char *argv[]) {
if (argc > 1) {
vulnerable_function(argv[1]);
}
return ;
}
If this was the issue, an attacker could send a long input to overflow buffer and execute malicious code. But for CVE-2021-33152, there is no such vulnerable function.
How Can You Track CVEs Responsibly? ##
It’s important to read the CVE record. CVEs marked as “REJECTED” can be safely ignored in your vulnerability management. This stops you from wasting time on “phantom” issues.
Official CVE resources include
Summary ##
* CVE-2021-33152 doesn’t point to any real-world bug—it was never used.
* If you find it in a scanner report or database, it’s safe to ignore.
* Always check for the “REJECTED” status in vulnerability records!
References ##
1. CVE-2021-33152 on CVE MITRE
2. NVD Entry on CVE-2021-33152
3. What is a REJECTED CVE? (Official FAQ)
> Bottom line: CVE-2021-33152 is a placeholder. There’s nothing to fix or patch—move on to the next real issue!
Timeline
Published on: 01/01/1976 00:00:00 UTC
Last modified on: 09/04/2025 00:40:36 UTC