CVE-2015-7705
highpriority · track · 43EPSS 0.122 · 96 %ileDEEURUUSEPSS · scored 2026-10-23
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 impact via a large number of crafted requests.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedSIMA² Master Stationauma_psirt
Upgrade your SIMA2 to software version 2.6 or above. The NTP service of the SIMA2 Master Station with software version V2.6 and above includes a current, supported version of ntpd.
- MitigationSIMATIC CP 443-1 OPC UAsiemens_psirt
Configure an additional firewall to prevent communication to port udp/123 of an affected device
- MitigationSIMA² Master Stationauma_psirt
1. If your SIMA2 does not need to provide time information to other systems or synchronize itself with an NTP server, disable the NTP client on those systems. Please note that the NTP client is disabled by default in SIMA2 2. In case you must use the NTP server on an SIMA2, choose from the following options to reduce NTP-based risks: - Allow NTP traffic to/from trusted NTP clients only - Monitor the network for malicious NTP traffic going to/coming from the SIMA2 - Filter malicious NTP traffic going to/coming from the SIMA2 Monitor NTP server operations on your SIMA2 (server availability, correctness of advertised time, NTP-related log entries, etc.) 3. In case you must use the NTP client on an SIMA2, choose from the following options to reduce NTP-based risks: - Use trusted NTP servers only - Allow NTP traffic to/from trusted NTP servers only - Monitor the network for malicious NTP traffic targeting the SIMA2 - Filter malicious NTP traffic targeting the SIMA2 - Monitor NTP client operations on your SIMA2 (correctness of system time, NTP-related log entries, etc.)
- MitigationSIMATIC CP 443-1 OPC UAcisa_csaf_ot
Configure an additional firewall to prevent communication to port udp/123 of an affected device
- WorkaroundSIPLUS NET TIM 4R-IE (6AG1800-4BA00-7AA0)siemens_psirt
Configure an additional firewall to prevent communication to the port udp/123 of an affected device.
- WorkaroundSIPLUS NET TIM 4R-IE DNP3 (6AG1803-4BA00-7AA0)siemens_psirt
Configure an additional firewall to prevent communication to the port udp/123 of an affected device.
- WorkaroundTIM 4R-IE (6NH7800-4BA00)siemens_psirt
Configure an additional firewall to prevent communication to the port udp/123 of an affected device.
- WorkaroundTIM 4R-IE DNP3 (6NH7803-4BA00-0AA0)siemens_psirt
Configure an additional firewall to prevent communication to the port udp/123 of an affected device.
- WorkaroundSIPLUS NET TIM 4R-IE (6AG1800-4BA00-7AA0)cisa_csaf_ot
Configure an additional firewall to prevent communication to the port udp/123 of an affected device.
- WorkaroundSIPLUS NET TIM 4R-IE DNP3 (6AG1803-4BA00-7AA0)cisa_csaf_ot
Configure an additional firewall to prevent communication to the port udp/123 of an affected device.
- WorkaroundTIM 4R-IE (6NH7800-4BA00)cisa_csaf_ot
Configure an additional firewall to prevent communication to the port udp/123 of an affected device.
- WorkaroundTIM 4R-IE DNP3 (6NH7803-4BA00-0AA0)cisa_csaf_ot
Configure an additional firewall to prevent communication to the port udp/123 of an affected device.
- No fix plannedSIMATIC CP 443-1 OPC UAsiemens_psirt
Currently no remediation is planned
- No fix plannedSIPLUS NET TIM 4R-IE (6AG1800-4BA00-7AA0)siemens_psirt
Currently no fix is planned
- No fix plannedSIPLUS NET TIM 4R-IE DNP3 (6AG1803-4BA00-7AA0)siemens_psirt
Currently no fix is planned
- No fix plannedTIM 4R-IE (6NH7800-4BA00)siemens_psirt
Currently no fix is planned
- No fix plannedTIM 4R-IE DNP3 (6NH7803-4BA00-0AA0)siemens_psirt
Currently no fix is planned
- No fix plannedSIPLUS NET TIM 4R-IE (6AG1800-4BA00-7AA0)cisa_csaf_ot
Currently no fix is planned
- No fix plannedSIPLUS NET TIM 4R-IE DNP3 (6AG1803-4BA00-7AA0)cisa_csaf_ot
Currently no fix is planned
- No fix plannedTIM 4R-IE (6NH7800-4BA00)cisa_csaf_ot
Currently no fix is planned
- No fix plannedTIM 4R-IE DNP3 (6NH7803-4BA00-0AA0)cisa_csaf_ot
Currently no fix is planned
- No fix plannedSIMATIC CP 443-1 OPC UAcisa_csaf_ot
Currently no remediation is planned
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (31)
Products and version ranges known to be affected.
advisories (5)
Vendor and ecosystem advisories describing this.
- SSA-211752SSA-211752: Multiple NTP-Client Related Vulnerabilities in SIMATIC CP 443-1 OPC UA2021-06-08csaf · siemens_psirtDE
All versions of the SIMATIC CP 443-1 OPC UA contain multiple vulnerabilities in the underlying third party component NTP. Siemens recommends specific countermeasures for products where updates are not, or not yet available.
- SSA-497656SSA-497656: Multiple NTP Vulnerabilities in TIM 4R-IE Devices2021-04-13csaf · siemens_psirtDE
TIM 4R-IE devices contain multiple vulnerabilities in the integrated NTP component as listed below. Siemens recommends specific countermeasures for products where fixes are not, or not yet available.
- VDE-2022-032AUMA: Multiple Vulnerabilities in Automation Runtime NTP Service2022-08-09csaf · auma_psirtDE
The SIMA2 Master Station features an NTP service based on ntpd, a reference implementation of the Network Time Protocol (NTP). Affected SIMA2 Master Stations with software version < V2.6 include an outdated version of ntpd which is affected by a large number of vulnerabilities
- ICSA-21-103-11Siemens TIM 4R-IE Devices2021-04-13icsa · cisa_csaf_otUS
TIM 4R-IE devices contain multiple vulnerabilities in the integrated NTP component as listed below. Siemens recommends specific countermeasures for products where fixes are not, or not yet available.
- ICSA-21-159-11Siemens SIMATIC NET CP 443-1 OPC UA2021-06-08icsa · cisa_csaf_otUS
All versions of the SIMATIC CP 443-1 OPC UA contain multiple vulnerabilities in the underlying third party component NTP. Siemens recommends specific countermeasures for products where updates are not, or not yet available.
also known as (7)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (109)
External citations — patches, advisories, analysis.
- http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00020.htmlcnnvd
- http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00034.htmlcnnvd
- http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00037.htmlcnnvd
- http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00048.htmlcnnvd
- http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00052.htmlcnnvd
- http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00001.htmlcnnvd
- http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00020.htmlcnnvd
- http://lists.opensuse.org/opensuse-security-announce/2016-07/msg00026.htmlcnnvd
Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.
Free scan