CVE-2021-1593
CVE-2021-1593 is a high-severity vulnerability in Cisco Packet Tracer with a CVSS 3.x base score of 7.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-427.
Key facts
- Severity: High (CVSS 3.x base score 7.3)
- CVSS v2: 6.9
- EPSS exploit prediction: 0% (24th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-427
- Affected product: Cisco Packet Tracer
- Published:
- Last modified:
Description
A vulnerability in Cisco Packet Tracer for Windows could allow an authenticated, local attacker to perform a DLL injection attack on an affected device. To exploit this vulnerability, the attacker must have valid credentials on the Windows system. This vulnerability is due to incorrect handling of directory paths at run time. An attacker could exploit this vulnerability by inserting a configuration file in a specific path on the system, which can cause a malicious DLL file to be loaded when the application starts. A successful exploit could allow an attacker with normal user privileges to execute arbitrary code on the affected system with the privileges of another user’s account.
Frequently asked questions
- What is CVE-2021-1593?
- A vulnerability in Cisco Packet Tracer for Windows could allow an authenticated, local attacker to perform a DLL injection attack on an affected device. To exploit this vulnerability, the attacker must have valid credentials on the Windows system. This vulnerability is due to incorrect handling of directory paths at run time. An attacker could exploit this vulnerability by inserting a configuration file in a specific path on the system, which can cause a malicious DLL file to be loaded when the application starts. A successful exploit could allow an attacker with normal user privileges to execute arbitrary code on the affected system with the privileges of another user’s account.
- How severe is CVE-2021-1593?
- CVE-2021-1593 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-1593 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-1593?
- CVE-2021-1593 primarily affects Cisco Packet Tracer. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-1593?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-1593 published?
- CVE-2021-1593 was published on 2021-08-04 and last updated on 2026-06-17.
References
Affected products (6)
- cpe:2.3:a:cisco:packet_tracer:7.2.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:packet_tracer:7.2.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:packet_tracer:7.2.2:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:packet_tracer:7.3.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:packet_tracer:7.3.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:packet_tracer:8.0:*:*:*:*:*:*:*
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