An exploitable return of stack variable address vulnerability exists in the JavaScript implementation of Nitro Pro PDF. A specially crafted document can cause a stack variable to go out of scope, resulting in the application dereferencing a stale pointer. This can lead to code execution under the context of the application. An attacker can convince a user to open a document to trigger the vulnerability.
This vulnerability is classified as high severity with a CVSS score of 7.8. The risk to organizations includes potential unauthorized code execution, which can compromise sensitive information and disrupt operations. Given the nature of this vulnerability, users are likely to be targeted through social engineering tactics to open malicious documents.
Currently, there are no known exploits available for this vulnerability, but its high CVSS score warrants immediate attention. Organizations should prioritize patching to mitigate risks associated with this vulnerability.
Organizations should address this vulnerability in their priority patch cycle to avoid potential exploitation.
Vulnerability Details
The vulnerability allows attackers to execute arbitrary code by leveraging a flaw in the JavaScript implementation of Nitro Pro. The CVE was published on September 15, 2021, and affects the following versions of Nitro Pro: 13.31.0.605 and 13.33.2.645.
The vendor has classified this vulnerability as CWE-562: Return of Stack Variable Address, indicating a critical flaw in memory handling. The CVSS version 3.1 vector string for this vulnerability is CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
Technical Analysis
The root cause of this vulnerability stems from improper handling of stack variables in the JavaScript execution context. The attack vector is local, requiring the user to open a specially crafted document. The complexity of the attack is low, and no privileges are required to trigger the vulnerability, although user interaction is mandatory.
The potential impacts include high confidentiality, integrity, and availability risks due to the ability of attackers to execute arbitrary code within the application context.
Risk & Impact Analysis
The real-world risk posed by this vulnerability is significant. Organizations using Nitro Pro are at risk of unauthorized access and data breaches if the vulnerability is exploited. The potential blast radius is substantial, as successful exploitation could allow an attacker to gain control over the affected system and access sensitive information.
Given the CVSS score of 7.8 and the absence of known public exploits, organizations should prioritize remediation efforts and ensure that users are educated on the risks of opening unknown documents. This vulnerability is not currently listed in the KEV catalog, but its potential for exploitation remains a concern.
Signal | Status |
|---|---|
Known Exploit | No |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The following versions of Nitro Pro are affected by this vulnerability: 13.31.0.605 and 13.33.2.645. Organizations should ensure that they are using patched versions to mitigate the risk.
Mitigation & Remediation
Organizations should prioritize patching Nitro Pro to versions that address this vulnerability. If immediate patching is not feasible, consider implementing network controls to restrict document access and educate users about the risks of opening untrusted files. Regular security assessments and penetration testing can also help identify and mitigate such vulnerabilities.
For further guidance, organizations may refer to resources on penetration testing and security best practices.
Detection Guidance
To detect potential exploitation of this vulnerability, organizations should monitor for unusual application behavior and log indicators associated with document handling. Behavioral anomalies in Nitro Pro usage may also indicate attempts to exploit this flaw.
AppSecure Threat Intelligence Insight
The long-term significance of CVE-2021-21798 highlights the necessity for organizations to maintain robust security postures and remain vigilant against emerging threats. This vulnerability serves as a reminder of the importance of secure coding practices to prevent memory handling errors.
Organizations should also consider engaging in regular security assessments to uncover vulnerabilities before attackers can exploit them. For further information on security assessments, organizations can explore our application security assessment services.
Additionally, engaging in continuous penetration testing can help organizations stay ahead of potential threats.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
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