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No exploitation reported

CVE-2021-20109

No exploitation reported by the sources we read.

  • Published2021-07-19
  • WeaknessCWE-787

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

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.

Timeline

dates in UTC
  1. 2021-07-1915:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-20109?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-20109?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Zohocorp manageengine assetexplorer
BranchAffectedFixed in
1.0= 1.0.34no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

No fix published by the sources we read yet. NVD record

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub

Sources

  • NVDCVSS 3.17.5read 2026-10-23
  • NVDCVSS 2.05read 2026-10-23
  • NVDweakness (CWE)CWE-787read 2026-10-23
  • FIRST EPSSEPSS score1.4 %2026-10-23

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Published
2021-07-19
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2021-20109?

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.

Is CVE-2021-20109 actively exploited?

Active exploitation of CVE-2021-20109 has not been confirmed. Its EPSS score was 1.4% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

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

CVE-2021-20109 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

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