How severe is CVE-2013-6920?

CVE-2013-6920 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-2013-6920 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-6920?

CVE-2013-6920 primarily affects Siemens Sinamics S/g Family Firmware. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2013-6920?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2013-6920 published?

CVE-2013-6920 was published on 2013-12-07 and last updated on 2026-06-17.

CVE-2013-6920

CVE-2013-6920 is a critical-severity vulnerability in Siemens Sinamics S/g Family Firmware with a CVSS 2.0 base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Siemens Sinamics S/g Family Firmware
Published: 2013-12-07
Last modified: 2026-06-17

Description

Siemens SINAMICS S/G controllers with firmware before 4.6.11 do not require authentication for FTP and TELNET sessions, which allows remote attackers to bypass intended access restrictions via TCP traffic to port (1) 21 or (2) 23.

Frequently asked questions

What is CVE-2013-6920?: Siemens SINAMICS S/G controllers with firmware before 4.6.11 do not require authentication for FTP and TELNET sessions, which allows remote attackers to bypass intended access restrictions via TCP traffic to port (1) 21 or (2) 23.
How severe is CVE-2013-6920?: CVE-2013-6920 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2013-6920 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-6920?: CVE-2013-6920 primarily affects Siemens Sinamics S/g Family Firmware. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2013-6920?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2013-6920 published?: CVE-2013-6920 was published on 2013-12-07 and last updated on 2026-06-17.

References

Affected products (14)

cpe:2.3:o:siemens:sinamics_s\/g_family_firmware:*:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_g110:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_g110d:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_g120:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_g120c:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_g120d:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_g120p:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_g130:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_g150:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_g180:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_s110:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_s120:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_s120cm:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sinamics_s150:-:*:*:*:*:*:*:*

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