CVE-2023-26553

mediumpriority · track · 22EPSS 0.007 · 53 %ileDEEUNLRUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.70% (53rd) EPSS

CVSS 5.6 · medium

Is it mine?

113 products

Check your exposure

Who says so?

8 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

mstolfp in libntp/mstolfp.c in NTP 4.2.8p15 has an out-of-bounds write when copying the trailing number. An adversary may be able to attack a client ntpq process, but cannot attack ntpd.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedSITOP UPS1600 10 A Ethernet/ PROFINET (6EP4134-3AB00-2AY0)siemens_psirt
Update to V2.5.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/79207181/
FixedSITOP UPS1600 20 A Ethernet/ PROFINET (6EP4136-3AB00-2AY0)siemens_psirt
Update to V2.5.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/79207181/
FixedSITOP UPS1600 40 A Ethernet/ PROFINET (6EP4137-3AB00-2AY0)siemens_psirt
Update to V2.5.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/79207181/
FixedSITOP UPS1600 EX 20 A Ethernet PROFINET (6EP4136-3AC00-2AY0)siemens_psirt
Update to V2.5.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/79207181/
Fixedphoenix_contact_psirt
Update to the latest 2024.0.6 LTS Firmware Release. PHOENIX CONTACT recommends to always use an up-to-date version of the PLCnext Engineer.
FixedSITOP UPS1600 10 A Ethernet/ PROFINET (6EP4134-3AB00-2AY0)cisa_csaf_ot
Update to V2.5.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/79207181/
FixedSITOP UPS1600 20 A Ethernet/ PROFINET (6EP4136-3AB00-2AY0)cisa_csaf_ot
Update to V2.5.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/79207181/
FixedSITOP UPS1600 40 A Ethernet/ PROFINET (6EP4137-3AB00-2AY0)cisa_csaf_ot
Update to V2.5.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/79207181/
FixedSITOP UPS1600 EX 20 A Ethernet PROFINET (6EP4136-3AC00-2AY0)cisa_csaf_ot
Update to V2.5.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/79207181/

cvss

Technical severity, 0–10. One row per scoring source.

5.6

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.15.6mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lprimary · NVD / NIST USexploitability 2.2 · impact 3.4

v3.15.6mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · CISA US

v3.15.6mediumAV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · FSTEC (BDU) RU

v3.15.6mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · ENISA EU

v3.15.6mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondaryexploitability 2.2 · impact 3.4

v3.15.6mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · Siemens ProductCERT DE

v3.15.6mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · Phoenix Contact PSIRT DE

v3.15.1mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:Usecondary · CVSS-BT (t0sche)

v3.15.6mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · NCSC-NL NL

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-787USprimaryCWE-787USCWE-787USCWE-787USCWE-787USCWE-787US

affected products (113)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Broadcom Brocade SANnavall versionscert_bundDEcpe:/a:broadcom:brocade_sannav:-
Broadcom Fabric OSall versionscert_bundDEcpe:/o:broadcom:fabric_operating_system:-
Broadcom Fabric OS <8.2.3eall versionscert_bundDE
Broadcom Fabric OS <9.1.1dall versionscert_bundDE
Broadcom Fabric OS <9.2.0ball versionscert_bundDE
Broadcom Fabric OS <9.2.1all versionscert_bundDE
Dell Avamarall versionscert_bundDEcpe:/a:dell:avamar:-
Dell Avamar <19.12all versionscert_bundDE
Dell NetWorker <vproxy 19.8.0.3all versionscert_bundDE
Dell NetWorker <vproxy 19.9.0.2all versionscert_bundDE
Dell NetWorker Virtual Editionall versionscert_bundDEcpe:/a:dell:networker:virtual_edition
Fedora Linuxall versionscert_bundDEcpe:/o:fedoraproject:fedora:-
Gentoo Linuxall versionscert_bundDEcpe:/o:gentoo:linux:-
HPE HP-UX NTP <C.4.2.8.7.0all versionscert_bundDE
IBM AIX 7.2all versionscert_bundDEcpe:/o:ibm:aix:7.2
IBM AIX 7.3all versionscert_bundDEcpe:/o:ibm:aix:7.3
IBM VIOS 3.1all versionscert_bundDEcpe:/a:ibm:vios:3.1
Meinberg LANTIME <V7.06.014all versionscert_bundDE
Open Source ntp 4.2.8p15all versionscert_bundDEcpe:/a:ntp:ntp:4.2.8p15

showing 20 of 113

advisories (6)

Vendor and ecosystem advisories describing this.

NCSC-2024-0246Kwetsbaarheden verholpen in Siemens productenNL2024-06-11csaf · ncsc_nlNL
Siemens heeft kwetsbaarheden verholpen in diverse producten, zoals SCALANCE, SICAM, Tecnomatix, SITOP en PowerSys.
NCSC-2024-0411Kwetsbaarheden verholpen in Oracle Database productenNL2024-10-17csaf · ncsc_nlNL
Oracle heeft kwetsbaarheden verholpen in diverse Database producten en subsystemen, zoals de Core database, Application Express, Autonomous Health Framework, Essbase, GoldenGate, SQL Developer en Secure Backup.
SSA-238730SSA-238730: Out-of-Bounds Write Vulnerabilities in SITOP UPS1600 before V2.5.42024-06-11csaf · siemens_psirtDE
Multiple out-of-bounds vulnerabilities in third-party components are affecting SITOP UPS1600 before V2.5.4. Attackers could exploit these vulnerabilities and cause limited impact in the affected systems. Siemens has released new versions for the affected products and recommends to update to the latest versions.
VDE-2024-073Phoenix Contact: Multiple Vulnerabilities in PLCnext Firmware2024-12-09csaf · phoenix_contact_psirtDE
Multiple Linux component vulnerabilities fixed in latest PLCnext Firmware release 2024.0.6 LTS
WID-SEC-W-2023-0938ntp: Mehrere SchwachstellenDeutsch2023-04-11csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in ntp ausnutzen, um nicht näher definierte Auswirkungen zu erreichen. Die Ausnutzung erfordert eine bestimmte Konfiguration und ggf. das Mitwirken eines Administrators, beispielsweise durch Social Engineering.
ICSA-24-165-05Siemens SITOP UPS16002024-06-11icsa · cisa_csaf_otUS
Multiple out-of-bounds vulnerabilities in third-party components are affecting SITOP UPS1600 before V2.5.4. Attackers could exploit these vulnerabilities and cause limited impact in the affected systems. Siemens has released new versions for the affected products and recommends to update to the latest versions.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund ncsc_nl siemens_psirt phoenix_contact_psirt cisa_csaf_ot NVD CVE.org MITRE

published 2023-04-11modified 2026-06-17

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+16119 more

references (9)

External citations — patches, advisories, analysis.

scry

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