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CVE-2018-8956 (GCVE-0-2018-8956)

Vulnerability from cvelistv5 – Published: 2020-05-06 18:03 – Updated: 2024-08-05 07:10
VLAI
Summary
ntpd in ntp 4.2.8p10, 4.2.8p11, 4.2.8p12 and 4.2.8p13 allow remote attackers to prevent a broadcast client from synchronizing its clock with a broadcast NTP server via soofed mode 3 and mode 5 packets. The attacker must either be a part of the same broadcast network or control a slave in that broadcast network that can capture certain required packets on the attacker's behalf and send them to the attacker.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE
  • n/a
Assigner
References
Show details on NVD website
To clipboard 

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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2025-11-21T16:54:51+00:00",
      "cve": "CVE-2018-8956",
      "id": "CVE-2018-8956",
      "initial_release_date": "2018-01-01T00:00:00+00:00",
      "product_status:known_not_affected": "12",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "ntp: ntpd allows remote attackers to prevent a broadcast client from synchronizing its clock",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2018/cve-2018-8956.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-31T08:46:38Z",
      "cve": "CVE-2018-8956",
      "id": "CVE-2018-8956",
      "initial_release_date": "2023-02-15T04:28:57Z",
      "product_status:known_affected": "20",
      "product_status:recommended": "105",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2018-8956",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2018-8956.json",
      "version": "12"
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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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