Skip to content
Noroxi
CVE-2013-5211· NVD / CVE Program· CNA mitre

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 amplificat

Noroxi assessment

Priority: Plan (action score 49/100)

  • A ready-made attack module is public (Metasploit); exploiting it takes no special expertise.
  • Public proof-of-concept code exists (Exploit-DB, GitHub); there is no record of exploitation in the wild.
  • Probability of exploitation in the next 30 days: 97.5% (FIRST EPSS); higher than 99.9% of all records.
  • No special conditions are required; it is repeatable.
  • Fixed version: ntp (Debian:11) 1:4.2.8p3+dfsg-1; ntp (openSUSE:Tumbleweed) 4.2.8p9-1.1.

Add it to your regular patch cycle. Upgrade to ntp (Debian:11) 1:4.2.8p3+dfsg-1; ntp (openSUSE:Tumbleweed) 4.2.8p9-1.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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.

MediumCVSS 5.0 · v2.0—Weaponized Fix available
Published
Jan 2, 2014
Updated
Jun 16, 2026
EPSS
97.5% · 99th percentile

Report tools

JSON

Action score

49

Plan

Add it to your regular patch cycle.

CVSS
20 / 40 · 5.0 / 10
CISA KEV
0 / 30 · Not listed
EPSS
29 / 30 · 97.5%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • Weaponized exploit exists
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2013-5211

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for ntp records

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
ntpntp
opensuseopensuse
oraclelinux

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • ntp ntpbefore 4.2.7
  • ntp ntp4.2.7
  • opensuse opensuse11.4
  • oracle linux6
  • oracle linux7

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:11ntpbefore 1:4.2.8p3+dfsg-11:4.2.8p3+dfsg-1
openSUSE:Tumbleweedntpbefore 4.2.8p9-1.14.2.8p9-1.1

Same product

ntp: all records

Other highest-scoring records for the same primary product.

  • CVE-2015-7871Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to bypass authentication.
    64This week
  • CVE-2014-9295Multiple stack-based buffer overflows in ntpd in NTP before 4.2.8 allow remote attackers to execute arbitrary code via a crafted packet, rel
    54Plan
  • CVE-2018-12327Stack-based buffer overflow in ntpq and ntpdc of NTP version 4.2.8p11 allows an attacker to achieve code execution or escalate to higher pri
    47Plan

Published before and after this one in the same product

  • ← EarlierCVE-2009-1252May 19, 2009 · Stack-based buffer overflow in the crypto_recv function in ntp_crypto.c in ntpd in NTP before 4.2.4p7 and 4.2.5 before 4.2.5p74, when OpenSS
    33Monitor
  • ← EarlierCVE-2009-3563Dec 9, 2009 · ntp_request.c in ntpd in NTP before 4.2.4p8, and 4.2.5, allows remote attackers to cause a denial of service (CPU and bandwidth consumption)
    40Plan
  • Later →CVE-2014-9293Dec 19, 2014 · The config_auth function in ntpd in NTP before 4.2.7p11, when an auth key is not configured, improperly generates a key, which makes it easi
    34Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
debian:ntp1:4.2.8p3+dfsg-1 · Debian:11Package registry (OSV)
opensuse:ntp4.2.8p9-1.1 · openSUSE:TumbleweedPackage registry (OSV)

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Evidence

  • Metasploit module ×10
  • Exploit-DB entry ×1
  • Proof-of-concept repository on GitHub ×5

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Exploit-DB entrydos2014-04-28
Metasploit moduleauxiliary/scanner/ntp/ntp_monlistNTP Monitor List Scannerauxiliary—
Metasploit moduleauxiliary/scanner/ntp/ntp_peer_list_dosNTP Mode 7 PEER_LIST DoS Scannerauxiliary2014-08-25
Metasploit moduleauxiliary/scanner/ntp/ntp_peer_list_sum_dosNTP Mode 7 PEER_LIST_SUM DoS Scannerauxiliary2014-08-25
Metasploit moduleauxiliary/scanner/ntp/ntp_readvarNTP Clock Variables Disclosureauxiliary—
Metasploit moduleauxiliary/scanner/ntp/ntp_req_nonce_dosNTP Mode 6 REQ_NONCE DRDoS Scannerauxiliary2014-08-25
Metasploit moduleauxiliary/scanner/ntp/ntp_reslist_dosNTP Mode 7 GET_RESTRICT DRDoS Scannerauxiliary2014-08-25
Metasploit moduleauxiliary/scanner/ntp/ntp_unsettrap_dosNTP Mode 6 UNSETTRAP DRDoS Scannerauxiliary2014-08-25
Metasploit moduleauxiliary/scanner/portmap/portmap_ampPortmapper Amplification Scannerauxiliary—
Metasploit moduleauxiliary/scanner/udp/udp_amplificationUDP Amplification Scannerauxiliary—
Metasploit moduleauxiliary/scanner/upnp/ssdp_ampSSDP ssdp:all M-SEARCH Amplification Scannerauxiliary—
Proof-of-concept repository on GitHubstars:152014-09-07

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. First PoC+116 d
  3. Metasploit+235 d
  4. TodayOct 23, 2026+4677 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
P · the service can be disrupted
Attack complexity
Low
Confidentiality impact
None
Integrity impact
None
Availability impact
P

Weakness class (CWE)

CWE-20 · Improper Input Validation

CVSS vector

AV:N/AC:L/Au:N/C:N/I:N/A:P

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (19 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records