What is the CVSS score of CVE-2021-20109?

CVE-2021-20109 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N. EPSS exploitation probability: 1.4%.

Manageengine Assetexplorer CVE-2021-20109

HIGH

Out-of-bounds Write (CWE-787)

2021-07-19 vulnreport@tenable.com

Buffer Overflow Memory Corruption Manageengine Assetexplorer

7.5

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

7.5 HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

Lifecycle Timeline

CVE Published

Jul 19, 2021 - 15:15 nvd

HIGH 7.5

DescriptionNVD

Due to the Asset Explorer agent not validating HTTPS certificates, an attacker on the network can statically configure their IP address to match the Asset Explorer's Server IP address. This will allow an attacker to send a NEWSCAN request to a listening agent on the network as well as receive the agent's HTTP request verifying its authtoken. In AEAgent.cpp, the agent responding back over HTTP is vulnerable to a Heap Overflow if the POST payload response is too large. The POST payload response is converted to Unicode using vswprintf. This is written to a buffer only 0x2000 bytes big. If POST payload is larger, then heap overflow will occur.

AnalysisAI

Due to the Asset Explorer agent not validating HTTPS certificates, an attacker on the network can statically configure their IP address to match the Asset Explorer's Server IP address. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

Technical ContextAI

This vulnerability is classified as Out-of-bounds Write (CWE-787), which allows attackers to write data beyond allocated buffer boundaries leading to code execution or crashes. Due to the Asset Explorer agent not validating HTTPS certificates, an attacker on the network can statically configure their IP address to match the Asset Explorer's Server IP address. This will allow an attacker to send a NEWSCAN request to a listening agent on the network as well as receive the agent's HTTP request verifying its authtoken. In AEAgent.cpp, the agent responding back over HTTP is vulnerable to a Heap Overflow if the POST payload response is too large. The POST payload response is converted to Unicode using vswprintf. This is written to a buffer only 0x2000 bytes big. If POST payload is larger, then heap overflow will occur. Affected products include: Zohocorp Manageengine Assetexplorer.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Validate write boundaries, use memory-safe languages, enable compiler protections (ASLR, stack canaries).