vciy

CVE-2016-1549

INDEX BUILT · 2026-09-20

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A malicious authenticated peer can create arbitrarily-many ephemeral associations in order to win the clock selection algorithm in ntpd in NTP…

CVE-2016-15494 of 4 sources documented this
19

rank 19 = 1 + 16 + 0 + 2 + 0

rank@v1 · backlog

Someone is already using it

CISA KEV catalog · public proof-of-concept · FIRST EPSS

EPSS 0.03147  ·  without this subject the record ranks 18

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 6.5, from NVD  ·  without this subject the record ranks 3

It is getting worse, not staying still

FIRST EPSS series, rescorings and bad loads removed

no persisting rise in 365 days  ·  without this subject the record ranks 19

How much of the world it touches

NVD CPE configurations

1 product in the CPE ranges  ·  without this subject the record ranks 17

Someone else already set the date

CISA KEV remediation due date

no CISA due date  ·  without this subject the record ranks 19

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$96,100over the next 30 days, if this record is yours
Movementno material movementthe record holds only daily drift and scoring model releases
Basisassumeda published average, not your estate

$96,100 = $4.99M incident cost x 0.6121449559255632 exposure x 0.03147 likelihood

udv@v1 · unaudited · wrong for you until you say what you run

$4.99M is the cost of a breach that happened, from IBM Cost of a Data Breach Report 2026, global average. It is not the value of any asset of yours. That average already covers breaches of every severity, so scaling it by exposure understates a partial-impact record. That is an assumption, not a measurement. Your own asset value goes in the decision record.

Hindsight · the state

0.03147EPSSNOT IN KEVas of 2026-09-20
Severity6.5 MEDIUMreceipt
Harmpartial impactreceipt
Exploitationnone in held sources
Defenseno fix version held
Movementrisenreceipt
PLATEAU10Minimal movement since 2022-02-04, 1675 days at 0.03, as of 2026-09-06. arc-rules@v1

Foresight · where to check next

No weakness class or product neighbourhood is held for this record, so this index cannot name anywhere to check next. That is an absence in the record, not a finding about the software.

Color is a claim, not decoration:the hostile worldthe defenseno signal

Running NTP? Check your version

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Harm, if it fires from the vector and the weakness

Written for the ticket you're about to file.

Reachnetwork-reachable · low privileges required · no user interaction · low attack complexityreceipt
ImpactComplete integrity lossreceipt
Scored fromCVSS v3.0 · NVD's vectorreceipt
Weakness classCWE-19receipt
Published consequencesMITRE publishes no common consequences for this weakness.[email protected]

CISA KEV & Federal Remediation Deadline from the record and CISA

The fix, and how long it's been waiting.

Fixed inNo fix version in held sources, as the index stood on 6 Sep 2026.
Patch available sinceNo dated patch-availability record in held sources. The index holds reference URLs without dates and only the current revision of the CVE record, so the day a fix first existed cannot be derived. Only the versions it landed in.

Exploit Status & Known PoCs a ladder, not a score

Current rung: Nothing observed in held sources.

  • RUNG 1Nothing observed in held sources
  • RUNG 2Proof-of-concept published
  • RUNG 3Exploited in the wild · CISA KEV listed
  • RUNG 4Ransomware campaign use known

Authority who says so

CVSS, NVD6.5 MEDIUMreceipt
Exploit probability0.03147 · top 13% of all CVEsreceipt
Blast breadth1 product across 1 vendorderived
Assigned bycertccreceipt
Recorded changes29 · last 19 Sep 2026derived

Affected & Fixed Versions as published

Affected productNTP Project NTP; NTPsec Project NTPSecreceipt
Published rangesntp 4.2.8receipt

A rung lights from a row in the index, never from an assessment. "Held sources" is the true scope of the claim: this index reads the CVE record, NVD, CISA KEV, FIRST's EPSS and public proof-of-concept repositories, and it does not observe attacks.

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What it is stated by the CNA

A malicious authenticated peer can create arbitrarily-many ephemeral associations in order to win the clock selection algorithm in ntpd in NTP 4.2.8p4 and earlier and NTPsec 3e160db8dc248a0bcb053b56a80167dc742d2b74 and a5fb34b9cc89b92a8fef2f459004865c93bb7f92 and modify a victim's clock. receipt

NVD's analysis a second authority

severity
6.5 CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
weakness
CWE-19
affected versions
ntp 4.2.8

check it yourself talosintelligence.com securityfocus.com securitytracker.com oracle.com security.netapp.com security.FreeBSD.org +3 morereceipt

Movement the material steps

4 Feb 20220.01282
7 Mar 20230.00131 · scoring model v2023.03.01
17 Mar 20250.00729 · scoring model v2025.03.14
15 Jun 20260.03121 · scoring model v2026.06.15
6 Sep 20260.03147
Show all 29 observations
4 Feb 20220.01282
7 Mar 20230.00131
18 Jun 20240.00186
17 Dec 20240.00172
17 Mar 20250.00729
29 Mar 20250.0197
30 Mar 20250.00729
19 Jun 20250.01045
13 Jul 20250.00981
10 Aug 20250.01045
28 Aug 20250.009
2 Sep 20250.01074
14 Sep 20250.01082
15 Sep 20250.01053
17 Nov 20250.00808
13 Dec 20250.00932
14 Dec 20250.00841
20 Dec 20250.00742
27 Dec 20250.00808
28 Dec 20250.00742
21 Jan 20260.00969
22 May 20260.00995
27 May 20260.00969
15 Jun 20260.03121
30 Jun 20260.03147
23 Aug 20260.03179
30 Aug 20260.03147
5 Sep 20260.03179
6 Sep 20260.03147

29 observations held. A highlighted step crossed a promotion threshold. A step marked with a scoring model moved because the instrument was replaced, not because the vulnerability changed. receipt

The full biography

EPSS 0.03147Published2017-01-06Index as of2026-09-06

The record had been public for 9 years, 8 months when this index was last written.

Published 2017-01-06 receipt · Index as of 2026-09-06 derived

Siblings and hubs

Records related to this one

Its defect family

ntp project ntp

Grouped by shared product and weakness, not by shared vulnerability. Each record's own state is on its own page.

Family membership: held values

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Browse the index from here

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What usually comes next

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