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CVE-2021-21002 (GCVE-0-2021-21002)

Vulnerability from cvelistv5 – Published: 2021-06-25 18:25 – Updated: 2024-09-17 03:58
VLAI
Title
Denial of Service in Phoenix Contact FL COMSERVER UNI products
Summary
In Phoenix Contact FL COMSERVER UNI in versions < 2.40 a invalid Modbus exception response can lead to a temporary denial of service.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-772 - Missing Release of Resource after Effective Lifetime
Assigner
References
Impacted products
Vendor Product Version CPE status
Phoenix Contact FL COMSERVER Affected: UNI 232/422/485 (2313452) , < 2.40 (custom)
Affected: UNI 232/422/485-T (2904817) , < 2.40 (custom)
guessed Create a notification for this product.
Date Public
2021-06-23 00:00
Credits
This vulnerability was found by Petri Tuomio and reported to PHOENIX CONTACT by Waertsilae PSIRT. PHOENIX CONTACT thanks CERT@VDE for the coordination and support with this publication.
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    "redhat_vex": {
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      "cve": "CVE-2021-21002",
      "id": "CVE-2021-21002",
      "initial_release_date": "2021-06-23T00:00:00+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "Denial of Service in Phoenix Contact FL COMSERVER UNI products",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-21002.json",
      "version": "3"
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  }
}



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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

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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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