CVE-2013-5211

MEDIUMCVSS v2 · 5.05.0—
EchelonGraph scoreLOW confidence

This CVE was only ever scored under CVSS v2.0. NVD CVSS v2.0 base 5.0 — v2 rates that MEDIUM (v2 bands: LOW 0.0–3.9 / MEDIUM 4.0–6.9 / HIGH 7.0–10.0; v2 has no CRITICAL band). Vector AV:N/AC:L/Au:N/C:N/I:N/A:P. CVSS v2 is an older, coarser metric than v3.1/v4.0 (no Scope, no User Interaction, no Attack Requirements), so it is not directly comparable to a v3 or v4 score. NVD has never re-scored this record under v3. EPSS predicts 97.5% exploitation probability in the next 30 days, which is reflected in EG Risk but does not lift the v2 base. Confidence: LOW.

Sources: epss, nvd_v2
Weaponized
5.0EG
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 98%
  • Public exploit code is available (Metasploit, epss top5pct, epss high, public exploit)
CISA-KEV: Not listedEPSS PROB: 98%CVSS v2: 5.0Exploit: Metasploit · epss top5pct · epss high · public exploitExposed services: Not assessed

A fix is available — apply it.

The monlist feature in ntp_request.c in ntpd in NTP before 4.2.7p26 allows remote attackers to cause a denial of service (traffic amplification) via forged (1) REQ_MON_GETLIST or (2) REQ_MON_GETLIST_1 requests, as exploited in the wild in December 2013.

CVSS v2.0 (legacy)
5.0MEDIUMNVD never assigned a CVSS v3 rating to this CVE
EG Score
5.0MEDIUMlow confidence
EG Risk
66
EG Risk 66/100CISA SSVC

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity50% × 45%
Exploitation98% × 40%
Automatability30% × 15%
CISA SSVC: Track at low, Track or Track* at medium and Track* or Attend at high mission impact.
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
98%
EPSS %ILE
99th
KEV
Not listed

CISA SSVCTrack at low, Track or Track* at medium and Track* or Attend at high mission impact.

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (EG-KEV: weaponized) · Automatable unknown (not published for this CVE) · Technical impact unknown (not published for this CVE). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

January 2, 2014

Last Modified

April 29, 2026

References (42)

Affected Packages

(1 across 1 ecosystem)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
ntp—
  • every version up to 1:4.2.8p3+dfsg-1: fixed in 1:4.2.8p3+dfsg-1
—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 2× in last 7d / 7× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-10-01 05:10 UTCOSV refresh
  2. 2026-09-30 00:14 UTCEG score recompute
  3. 2026-09-27 13:39 UTCEPSS rescore
  4. 2026-09-26 15:53 UTCEPSS rescore
  5. 2026-09-21 20:25 UTCEPSS rescore
  6. 2026-09-17 19:21 UTCEPSS rescore
  7. 2026-09-12 07:10 UTCOSV refresh
  8. 2026-08-30 19:12 UTCEPSS rescore
  9. 2026-08-24 12:30 UTCOSV refresh
  10. 2026-08-20 22:50 UTCEPSS rescore
  11. 2026-08-08 08:19 UTCOSV refresh
  12. 2026-07-30 16:23 UTCEPSS rescore
  13. 2026-07-26 13:48 UTCEG score recompute▲ 5.00
  14. 2026-07-23 01:16 UTCGHSA enrichment
  15. 2026-07-23 01:14 UTCGHSA enrichment
  16. 2026-07-23 01:12 UTCGHSA enrichment
  17. 2026-07-23 01:10 UTCEG score recompute▼ 9.00
  18. 2026-07-23 00:14 UTCEG score recompute
  19. 2026-07-22 21:52 UTCEG score recompute
  20. 2026-07-22 14:04 UTCEPSS rescore
  21. 2026-07-22 08:37 UTCOSV refresh
  22. 2026-07-15 01:56 UTCEPSS rescore
  23. 2026-07-05 03:51 UTCOSV refresh
  24. 2026-06-28 04:53 UTCEPSS rescore
  25. 2026-06-28 04:53 UTCEPSS rescore
Show 32 more
  1. 2026-06-23 21:30 UTCEPSS rescore
  2. 2026-06-23 21:30 UTCEPSS rescore
  3. 2026-06-16 17:49 UTCEPSS rescore
  4. 2026-06-16 17:49 UTCEPSS rescore
  5. 2026-06-16 17:49 UTCEPSS rescore
  6. 2026-06-16 15:14 UTCOSV refresh
  7. 2026-06-15 17:44 UTCEPSS rescore
  8. 2026-06-12 23:08 UTCEPSS rescore
  9. 2026-06-10 22:15 UTCEPSS rescore
  10. 2026-06-10 13:18 UTCEPSS rescore
  11. 2026-06-04 13:09 UTCEPSS rescore
  12. 2026-06-04 13:09 UTCEPSS rescore
  13. 2026-06-01 13:49 UTCEPSS rescore
  14. 2026-06-01 13:49 UTCEPSS rescore
  15. 2026-05-31 22:28 UTCEPSS rescore
  16. 2026-05-31 22:28 UTCEPSS rescore
  17. 2026-05-29 13:41 UTCEPSS rescore
  18. 2026-05-29 13:41 UTCEPSS rescore
  19. 2026-05-28 21:02 UTCEG score recompute
  20. 2026-05-28 21:02 UTCGHSA enrichment
  21. 2026-05-28 13:42 UTCEPSS rescore
  22. 2026-05-28 13:42 UTCEPSS rescore
  23. 2026-05-28 13:42 UTCEPSS rescore
  24. 2026-05-26 13:41 UTCEPSS rescore
  25. 2026-05-26 13:41 UTCEPSS rescore
  26. 2026-05-22 21:15 UTCEPSS rescore
  27. 2026-05-22 21:15 UTCEPSS rescore
  28. 2026-05-22 21:15 UTCEPSS rescore
  29. 2026-05-22 09:26 UTCOSV refresh
  30. 2026-05-21 22:39 UTCEPSS rescore
  31. 2026-05-18 21:29 UTCEPSS rescore
  32. 2026-05-18 21:29 UTCEPSS rescore

Publicly available exploits

(10 references)

Working exploit code is in the public domain (10 Metasploit modules). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • Metasploitauxiliary/scanner/ntp/ntp_peer_list_dos✓ verified
    First seen Aug 25, 2014

    NTP Mode 7 PEER_LIST DoS Scanner

    Open source ↗
  • Metasploitauxiliary/scanner/ntp/ntp_peer_list_sum_dos✓ verified
    First seen Aug 25, 2014

    NTP Mode 7 PEER_LIST_SUM DoS Scanner

    Open source ↗
  • Metasploitauxiliary/scanner/ntp/ntp_req_nonce_dos✓ verified
    First seen Aug 25, 2014

    NTP Mode 6 REQ_NONCE DRDoS Scanner

    Open source ↗
  • Metasploitauxiliary/scanner/ntp/ntp_reslist_dos✓ verified
    First seen Aug 25, 2014

    NTP Mode 7 GET_RESTRICT DRDoS Scanner

    Open source ↗
  • Metasploitauxiliary/scanner/ntp/ntp_unsettrap_dos✓ verified
    First seen Aug 25, 2014

    NTP Mode 6 UNSETTRAP DRDoS Scanner

    Open source ↗
  • Metasploitauxiliary/scanner/ntp/ntp_monlist✓ verified
    First seen Jan 1, 2013

    NTP Monitor List Scanner

    Open source ↗
  • Metasploitauxiliary/scanner/ntp/ntp_readvar✓ verified
    First seen Jan 1, 2013

    NTP Clock Variables Disclosure

    Open source ↗
  • Metasploitauxiliary/scanner/portmap/portmap_amp✓ verified
    First seen Jan 1, 2013

    Portmapper Amplification Scanner

    Open source ↗
  • Metasploitauxiliary/scanner/udp/udp_amplification✓ verified
    First seen Jan 1, 2013

    UDP Amplification Scanner

    Open source ↗
  • Metasploitauxiliary/scanner/upnp/ssdp_amp✓ verified
    First seen Jan 1, 2013

    SSDP ssdp:all M-SEARCH Amplification Scanner

    Open source ↗

Related CVEs(same product + same CWE)

Frequently asked(4)

What is CVE-2013-5211?
CVE-2013-5211 is a medium vulnerability published on January 2, 2014. The monlist feature in ntprequest.c in ntpd in NTP before 4.2.7p26 allows remote attackers to cause a denial of service (traffic amplification) via forged (1) REQMONGETLIST or (2) REQMONGETLIST1 requests, as exploited in the wild in December 2013.
When was CVE-2013-5211 disclosed?
CVE-2013-5211 was first published on January 2, 2014, with the most recent update on April 29, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2013-5211 actively exploited?
CVE-2013-5211 is not currently on CISA's Known Exploited Vulnerabilities catalog. EchelonGraph's EG-KEV model classifies it as weaponized: a functional public exploit exists. FIRST EPSS estimates a 98% probability of exploitation in the next 30 days (99th percentile of EPSS-scored CVEs).
How do I remediate CVE-2013-5211?
A fix for CVE-2013-5211 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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