CVE-2013-5211
MediumExploitedPublic exploitThe 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.
Published Jan 2, 2014 · Updated Aug 4, 2026 · Also known as DEBIAN-CVE-2013-5211
Key Facts
Patch immediately- CVE-2013-5211 is a medium-severity vulnerability (CVSS 5.0 v2) affecting Ntp, Opensuse, Linux (Oracle) and 4 more products.
- It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Jan 2, 2014. Public exploit code is available.
- EPSS estimates a 98% probability of exploitation in the next 30 days.
- Fixed versions are available, including Ntp 1:4.2.8p3+dfsg-1, Ntp 4.2.4p8-1.24.1, Ntp 4.2.4p8-1.26.1.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v2
5.0
AV:N/AC:L/Au:N/C:N/I:N/A:P
EPSS (30-day exploit likelihood)
98%
Higher than 99.9% of all scored CVEs
Exploited in the wild
Yes
2 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2013-5211 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Jan 2, 2014 | n/a | Not reported |
| CIRCL KEV | Jan 2, 2014 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
66 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| NtpNtp | 4.2.7, 4.2.7-p0, 4.2.7-p1, 4.2.7-p10, 4.2.7-p11, 4.2.7-p12, 4.2.7-p13, 4.2.7-p14 | 4.2.7 |
| OpensuseOpensuse | 11.4 | n/a |
| LinuxOracle | 6, 7 | n/a |
| ntpdateamazon | See advisory | 4.2.8p11-1.37.amzn1 |
| ntp-docamazon | See advisory | 4.2.8p11-1.37.amzn1 |
Patched Releases
Ntp
1:4.2.8p3+dfsg-1, 4.2.4p8-1.24.1, 4.2.4p8-1.26.1, 4.2.6p5-10.0.1.el6.1, 4.2.6p5-22.0.1.el7_2.2, 4.2.8p11-1.37.amzn1, 4.2.8p15-3.amzn2.0.4, 4.2.8p9-1.1, 4.2.7
ntp-doc
4.2.4p8-1.24.1, 4.2.4p8-1.26.1, 4.2.6p5-10.0.1.el6.1, 4.2.6p5-22.0.1.el7_2.2, 4.2.8p11-1.37.amzn1, 4.2.8p15-3.amzn2.0.4, 4.2.8p9-1.1
ntp-perl
4.2.6p5-10.0.1.el6.1, 4.2.6p5-22.0.1.el7_2.2, 4.2.8p11-1.37.amzn1, 4.2.8p15-3.amzn2.0.4
ntpdate
4.2.6p5-10.0.1.el6.1, 4.2.6p5-22.0.1.el7_2.2, 4.2.8p11-1.37.amzn1, 4.2.8p15-3.amzn2.0.4
sntp
4.2.6p5-22.0.1.el7_2.2, 4.2.8p15-3.amzn2.0.4
Timeline
Publicly disclosed
Jan 2, 2014
Added to Industry KEV feed
Jan 2, 2014
Added to CIRCL KEV
Jan 2, 2014
Last updated
Aug 4, 2026
Weakness Type
- CWE-20 Improper Input Validation
References
- advisoryhttp://aix.software.ibm.com/aix/efixes/security/ntp_advisory.asc
- advisoryhttp://ics-cert.us-cert.gov/advisories/ICSA-14-051-04
- advisoryopenSUSE-SU-2014:1149
- advisoryHPSBOV03505
- advisoryhttps://h20564.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c04790232
FAQ
Common Questions.
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.
Affected: Ntp versions 4.2.7, 4.2.7-p0, 4.2.7-p1, 4.2.7-p10, 4.2.7-p11, 4.2.7-p12, 4.2.7-p13, 4.2.7-p14; Opensuse versions 11.4; Linux (Oracle) versions 6, 7, among others. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Jan 2, 2014.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Ntp 1:4.2.8p3+dfsg-1, Ntp 4.2.4p8-1.24.1, Ntp 4.2.4p8-1.26.1.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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