CVE-2021-27500

mediumpriority · track · 30EPSS 0.013 · 71 %ileDEEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.35% (71st) EPSS
CVSS 5 · medium
Is it mine?
42 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · cisa_csaf_ot · festo_psirt

EPSS · scored 2026-10-27

A specifically crafted packet sent by an attacker to EIPStackGroup OpENer EtherNet/IP commits and versions prior to Feb 10, 2021 may result in a denial-of-service condition.

01

remediations

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

A vendor fix is available.

  • FixedOpENercisa_csaf_ot

    The maintainer of OpENer recommends those affected to apply the latest commits available

    https://github.com/EIPStackGroup/OpENer
  • Mitigationfesto_psirt

    - Minimize network exposure for all control system devices and/or systems, and ensure that they are not accessible from the Internet. - Deactivate EtherNet/IP in device settings if not used

  • Mitigationcisa_csaf_ot

    - Minimize network exposure for all control system devices and/or systems, and ensure that they are not accessible from the Internet. - Deactivate EtherNet/IP in device settings if not used

  • No fix plannedfesto_psirt

    There is no fix planned.

  • No fix plannedcisa_csaf_ot

    There is no fix planned.

02

cvss

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

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · CISA US
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ics-cert@hq.dhs.gov USexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · Festo PSIRT DE
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · CISA US
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU
03

ssvc

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

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-617USCWE-617USCWE-617US
05

affected products (42)

Products and version ranges known to be affected.

showing 20 of 42
06

advisories (3)

Vendor and ecosystem advisories describing this.

  • FSA-202101Festo: Multiple vulnerabilities in Ethernet/IP Stack of SBRD-Q/SBOC-Q/SBOI-Q2021-09-22csaf · festo_psirtDE

    The affected product families are cameras SBOC/SBOI and the Controller SBRD. The vulnerabilities are located within the Ethernet IP Stack from EIPStackGroup OpENer Ethernet/IP.

  • ICSA-21-105-02EIPStackGroup OpENer Ethernet/IP2021-04-15icsa · cisa_csaf_otUS

    Successful exploitation of these vulnerabilities could cause a denial-of-service condition and data exposure.

  • ICSA-25-273-02Festo SBRD-Q/SBOC-Q/SBOI-Q2021-09-22icsa · cisa_csaf_otUS

    The affected product families are cameras SBOC/SBOI and the Controller SBRD. The vulnerabilities are located within the Ethernet IP Stack from EIPStackGroup OpENer Ethernet/IP.

07

also known as (3)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdcisa_csaf_otfesto_psirtNVDCVE.orgMITRE
published 2022-05-12modified 2026-06-17
09

references (9)

External citations — patches, advisories, analysis.

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