CVE-2023-27533
highpriority · track · 36EPSS 0.022 · 82 %ileDEEURUUSEPSS · scored 2026-10-27
A vulnerability in input validation exists in curl <8.0 during communication using the TELNET protocol may allow an attacker to pass on maliciously crafted user name and "telnet options" during server negotiation. The lack of proper input scrubbing allows an attacker to send content or perform option negotiation without the application's intent. This vulnerability could be exploited if an application allows user input, thereby enabling attackers to execute arbitrary code on the system.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedSIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)siemens_psirt
Update to V3.1.5 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/ - FixedSIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)siemens_psirt
Update to V3.1.5 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/ - FixedSIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)siemens_psirt
Update to V3.1.5 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/ - FixedSIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)siemens_psirt
Update to V3.1.5 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/ - FixedSIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)siemens_psirt
Update to V3.1.5 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/ - FixedSINEC NMSsiemens_psirt
Update to V2.0 SP1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109826954/ - FixedSIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)cisa_csaf_ot
Update to V3.1.5 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/ - FixedSIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)cisa_csaf_ot
Update to V3.1.5 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/ - FixedSIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)cisa_csaf_ot
Update to V3.1.5 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/ - FixedSIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)cisa_csaf_ot
Update to V3.1.5 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/ - FixedSIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)cisa_csaf_ot
Update to V3.1.5 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/ - FixedSINEC NMScisa_csaf_ot
Update to V2.0 SP1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109826954/ - MitigationSIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)cisa_csaf_ot
Only build and run applications from trusted sources.
- MitigationSIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)cisa_csaf_ot
Only build and run applications from trusted sources.
- MitigationSIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)cisa_csaf_ot
Only build and run applications from trusted sources.
- MitigationSIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)cisa_csaf_ot
Only build and run applications from trusted sources.
- MitigationSIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)cisa_csaf_ot
Only build and run applications from trusted sources.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–critical · 3.1–9.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (93)
Products and version ranges known to be affected.
advisories (12)
Vendor and ecosystem advisories describing this.
- SSA-398330SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.52023-12-12csaf · siemens_psirtDE
Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the firmware version >= V3.1.0 and < V3.1.5 for the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP (incl. SIPLUS variant). These GNU/Linux vulnerabilities have been externally identified. Siemens has released new versions for the affected products and recommends to update to the latest versions. SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5 are no longer maintained and there won't be any update to the CVE list anymore. Please update to the latest version. Note: This SSA advises vulnerabilities for firmware version V3.1 only; for versions < V3.1 refer to Siemens Security Bulletin SSB-439005 (https://cert-portal.siemens.com/productcert/html/ssb-439005.html).
- SSA-943925SSA-943925: Multiple Vulnerabilities in SINEC NMS before V2.0 SP12024-02-13csaf · siemens_psirtDE
SINEC NMS before V2.0 SP1 is affected by multiple vulnerabilities. Siemens has released an update for SINEC NMS and recommends to update to the latest version.
- WID-SEC-W-2023-0690cURL: Mehrere SchwachstellenDeutsch2023-03-19csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in cURL ausnutzen, um Informationen offenzulegen, Sicherheitsvorkehrungen zu umgehen oder unbekannte Auswirkungen zu verursachen.
- WID-SEC-W-2023-1350Splunk Splunk Enterprise: Mehrere Schwachstellen in Komponenten von DrittanbieternDeutsch2023-06-01csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Splunk Splunk Enterprise in diversen Komponenten von Drittanbietern ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.
- WID-SEC-W-2023-1614Tenable Security Nessus Network Monitor: Mehrere SchwachstellenDeutsch2023-06-29csaf · cert_bundDE
Ein entfernter, anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Tenable Security Nessus Network Monitor ausnutzen, um beliebigen Code auszuführen, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand auszulösen und Daten zu manipulieren.
- WID-SEC-W-2023-2229Splunk Splunk Enterprise: Mehrere SchwachstellenDeutsch2023-08-30csaf · cert_bundDE
Ein entfernter, authentifizierter Angreifer kann mehrere Schwachstellen in Splunk Splunk Enterprise ausnutzen, um beliebigen Code auszuführen, einen 'Denial of Service'-Zustand zu verursachen, seine Privilegien zu erweitern und weitere, nicht spezifizierte Auswirkungen zu verursachen.
- WID-SEC-W-2024-0794Dell ECS: Mehrere SchwachstellenDeutsch2024-04-04csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Dell ECS ausnutzen, um seine Privilegien zu erweitern, beliebigen Programmcode mit Administratorrechten auszuführen, Informationen offenzulegen, Dateien zu manipulieren, einen Cross-Site-Scripting-Angriff durchzuführen, Sicherheitsvorkehrungen zu umgehen oder einen Denial of Service Zustand herbeizuführen.
- WID-SEC-W-2024-3377Dell PowerProtect Data Domain: Mehrere SchwachstellenDeutsch2024-11-07csaf · cert_bundDE
Ein lokaler Angreifer kann mehrere Schwachstellen in Dell PowerProtect Data Domain ausnutzen, um seine Privilegien zu erhöhen, Informationen offenzulegen und um nicht näher beschriebene Auswirkungen zu erzielen.
- WID-SEC-W-2026-0180Dell Data Protection Advisor: Mehrere SchwachstellenDeutsch2026-01-20csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Dell Data Protection Advisor ausnutzen, um beliebigen Code auszuführen, einen Denial-of-Service-Zustand zu erzeugen, Sicherheitsmaßnahmen zu umgehen und nicht näher spezifizierte Angriffe zu starten.
- ICSA-23-348-10Siemens SIMATIC S7-15002023-12-12icsa · cisa_csaf_otUS
Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the firmware version >= V3.1.0 and < V3.1.5 for the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP (incl. SIPLUS variant). These GNU/Linux vulnerabilities have been externally identified. Siemens has released new versions for the affected products and recommends to update to the latest versions. Note: This SSA advises vulnerabilities for firmware version V3.1 only; for versions < V3.1 refer to Siemens Security Bulletin SSB-439005 ( https://cert-portal.siemens.com/productcert/html/ssb-439005.html).
- ICSA-24-046-15Siemens SINEC NMS2024-02-13icsa · cisa_csaf_otUS
SINEC NMS before V2.0 SP1 is affected by multiple vulnerabilities. Siemens has released an update for SINEC NMS and recommends to update to the latest version.
- CURL-CVE-2023-27533TELNET option IAC injection2023-03-20vendor · osvUS
curl supports communicating using the TELNET protocol and as a part of this it offers users to pass on username and "telnet options" for the server negotiation. Due to lack of proper input scrubbing and without it being the documented functionality, curl would pass on username and telnet options to the server as provided. This could allow users to pass in carefully crafted content that pass on content or do option negotiation without the application intending to do so. In particular if an application for example allows users to provide the data or parts of the data.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (27)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2023-27533cnnvd
- https://curl.se/download.htmlPatchcnnvd
- https://cxsecurity.com/cveshow/CVE-2023-27533/cnnvd
- https://hackerone.com/reports/1891474cnnvd
- https://lists.debian.org/debian-lts-announce/2023/04/msg00025.htmlcnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/36NBD5YLJXXEDZLDGNFCERWRYJQ6LAQW/cnnvd
- https://security.gentoo.org/glsa/202310-12cnnvd
- https://security.netapp.com/advisory/ntap-20230420-0011/cnnvd
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