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CVE-2021-20617 (GCVE-0-2021-20617)

Vulnerability from cvelistv5 – Published: 2021-01-14 08:20 – Updated: 2024-08-03 17:45
VLAI Shadowserver Previdian
Summary
Improper access control vulnerability in acmailer ver. 4.0.1 and earlier, and acmailer DB ver. 1.1.3 and earlier allows remote attackers to execute an arbitrary OS command, or gain an administrative privilege which may result in obtaining the sensitive information on the server via unspecified vectors.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • Improper access control
Assigner
References
Impacted products
Vendor Product Version CPE status
Seeds Co.,Ltd. acmailer and acmailer DB Affected: acmailer ver. 4.0.1 and earlier, and acmailer DB ver. 1.1.3 and earlier
guessed Create a notification for this product.
Shadowserver
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: d6933dc8-b3a7-4bdc-8382-d3378299deb0

Vulnerability ID: CVE-2021-20617

Status: Confirmed

Status Updated: 2026-07-19 00:00 UTC

Exploited: Yes

Characteristics
Severity: 98.0
Timestamps
First Seen: 2024-12-05
Asserted: 2024-12-05
Last Seen: 2026-07-19
Scope
Asset Exposure: ['internet-facing']
Notes: Affected: acmailer / acmailer | Class: email | Severity: Critical (CVSS 9.8) | IoT: no | In CISA KEV: no | Honeypot connections on 2026-07-19: 1
Evidence

Type: Honeypot

Signal: In The Wild Attempts

Confidence: 70%

Source: shadowserver

Details
1D 1
Iot no
Feed Shadowserver Foundation honeypot/exploited-vulnerabilities
Type http-scan
Class email
7D Avg 0
Vendor acmailer
30D Avg 1
90D Avg 2
Product acmailer
Cisa Kev no
Connections 1
Observation Date 2026-07-19
Vulnerability Class CVSS
Vulnerability Score 9.8
Vulnerability Severity Critical
References
Created: 2026-06-30 09:23 UTC | Updated: 2026-07-21 01:01 UTC
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: f741db82-588c-4300-a2bd-00ed76a7ce55

Vulnerability ID: CVE-2021-20617

Status: Confirmed

Status Updated: 2021-01-14 08:20 UTC

Exploited: Yes

Timestamps
First Seen: 2021-01-14
Asserted: 2021-01-14
Scope
Notes: KEVIntel entry: Improper access control vulnerability in acmailer ver. 4.0.1 and earlier, and acmailer DB ver. 1.1.3 and earlier allows remote attackers to execute... | Affected: Seeds Co.,Ltd. / acmailer and acmailer DB | Used in malware: unknown | Not yet in CISA KEV: True
Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: kevintel

Details
Feed KEVIntel (kevintel.com)
Title Improper access control vulnerability in acmailer ver. 4.0.1 and earlier, and acmailer DB ver. 1.1.3 and earlier allows remote attackers to execute...
Vendor Seeds Co.,Ltd.
Product acmailer and acmailer DB
Added Date 2021-01-14T08:20:16.000Z
Cvss Score None
Epss Score None
Cvss Severity None
Epss Percentile None
Used In Malware unknown
Ahead Of Cisa Kev None
Not Yet In Cisa Kev True
References
Created: 2026-06-23 14:06 UTC | Updated: 2026-07-10 06:14 UTC
Show details on NVD website
To clipboard 

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Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.