Ntp
CVE-2015-7853
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Buffer copy size validation
MITRE ATT&CK
1 technique across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. EPSS exploitation probability: 40.56%. |
| Exploit ScenarioDerived | A remote attacker could overflow a buffer to corrupt adjacent memory by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
The datalen parameter in the refclock driver in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to execute arbitrary code or cause a denial of service (crash) via a negative. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Epss exploitation probability 40.6%.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Always validate buffer sizes before copy operations. Use bounded functions (strncpy, snprintf). Enable compiler protections.
Affects your stack
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Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Buffer Copy without Size Check (CWE-120), which allows attackers to overflow a buffer to corrupt adjacent memory. The datalen parameter in the refclock driver in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to execute arbitrary code or cause a denial of service (crash) via a negative input value. Affected products include: Ntp, Netapp Oncommand Balance, Netapp Oncommand Performance Manager, Netapp Oncommand Unified Manager, Netapp Clustered Data Ontap. Version information: before 4.2.8.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
The datalen parameter in the refclock driver in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to execute arbitrary code or cause a denial of service (crash) via a negative input value.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)CVE.org
Crypto-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 authen
The monlist feature in ntp_request.c in ntpd in NTP before 4.2.7p26 allows remote attackers to cause a denial of service
The read_mru_list function in NTP before 4.2.8p9 allows remote attackers to cause a denial of service (crash) via a craf
The decodenetnum function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause
Multiple stack-based buffer overflows in ntpd in NTP before 4.2.8 allow remote attackers to execute arbitrary code via a
ntpd in NTP before 4.2.8p8 allows remote attackers to cause a denial of service (daemon crash) via a crypto-NAK packet.
util/ntp-keygen.c in ntp-keygen in NTP before 4.2.7p230 uses a weak RNG seed, which makes it easier for remote attackers
The config_auth function in ntpd in NTP before 4.2.7p11, when an auth key is not configured, improperly generates a key,
NTP before 4.2.8p6 and 4.3.0 before 4.3.90 allows a remote attackers to cause a denial of service (stack exhaustion) via
The rate limiting feature in NTP 4.x before 4.2.8p4 and 4.3.x before 4.3.77 allows remote attackers to have unspecified
The panic_gate check in NTP before 4.2.8p5 is only re-enabled after the first change to the system clock that was greate
The receive function in ntp_proto.c in ntpd in NTP before 4.2.8 continues to execute after detecting a certain authentic
GitHub PoC
Exploit-DB