CVE-2016-8858

highpriority · attend · 50EPSS 0.295 · 98 %ileexploit · PoCDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

29.5% (98th) EPSS

CVSS 7.8 · high

Is it mine?

30 products

Check your exposure

Who says so?

7 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-26

The kex_input_kexinit function in kex.c in OpenSSH 6.x and 7.x through 7.3 allows remote attackers to cause a denial of service (memory consumption) by sending many duplicate KEXINIT requests. NOTE: a third party reports that "OpenSSH upstream does not consider this as a security issue."

remediations

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

A vendor fix is available.

FixedSCALANCE X204RNA (HSR) (6GK5204-0BA00-2MB2)siemens_psirt
Update to V3.2.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814809/
FixedSCALANCE X204RNA (PRP) (6GK5204-0BA00-2KB2)siemens_psirt
Update to V3.2.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814809/
FixedSCALANCE X204RNA EEC (HSR) (6GK5204-0BS00-2NA3)siemens_psirt
Update to V3.2.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814809/
FixedSCALANCE X204RNA EEC (PRP) (6GK5204-0BS00-3LA3)siemens_psirt
Update to V3.2.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814809/
FixedSCALANCE X204RNA EEC (PRP/HSR) (6GK5204-0BS00-3PA3)siemens_psirt
Update to V3.2.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814809/
FixedSCALANCE X204RNA (HSR) (6GK5204-0BA00-2MB2)cisa_csaf_ot
Update to V3.2.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814809/
FixedSCALANCE X204RNA (PRP) (6GK5204-0BA00-2KB2)cisa_csaf_ot
Update to V3.2.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814809/
FixedSCALANCE X204RNA EEC (HSR) (6GK5204-0BS00-2NA3)cisa_csaf_ot
Update to V3.2.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814809/
FixedSCALANCE X204RNA EEC (PRP) (6GK5204-0BS00-3LA3)cisa_csaf_ot
Update to V3.2.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814809/
FixedSCALANCE X204RNA EEC (PRP/HSR) (6GK5204-0BS00-3PA3)cisa_csaf_ot
Update to V3.2.7 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814809/
MitigationSCALANCE X204RNA (HSR) (6GK5204-0BA00-2MB2)siemens_psirt
Deactivate the webserver if not required, and if deactivation is supported by the product
MitigationSCALANCE X204RNA (PRP) (6GK5204-0BA00-2KB2)siemens_psirt
Deactivate the webserver if not required, and if deactivation is supported by the product
MitigationSCALANCE X204RNA EEC (HSR) (6GK5204-0BS00-2NA3)siemens_psirt
Deactivate the webserver if not required, and if deactivation is supported by the product
MitigationSCALANCE X204RNA EEC (PRP) (6GK5204-0BS00-3LA3)siemens_psirt
Deactivate the webserver if not required, and if deactivation is supported by the product
MitigationSCALANCE X204RNA EEC (PRP/HSR) (6GK5204-0BS00-3PA3)siemens_psirt
Deactivate the webserver if not required, and if deactivation is supported by the product
MitigationSCALANCE X204RNA (HSR) (6GK5204-0BA00-2MB2)cisa_csaf_ot
Deactivate the webserver if not required, and if deactivation is supported by the product
MitigationSCALANCE X204RNA (PRP) (6GK5204-0BA00-2KB2)cisa_csaf_ot
Deactivate the webserver if not required, and if deactivation is supported by the product
MitigationSCALANCE X204RNA EEC (HSR) (6GK5204-0BS00-2NA3)cisa_csaf_ot
Deactivate the webserver if not required, and if deactivation is supported by the product
MitigationSCALANCE X204RNA EEC (PRP) (6GK5204-0BS00-3LA3)cisa_csaf_ot
Deactivate the webserver if not required, and if deactivation is supported by the product
MitigationSCALANCE X204RNA EEC (PRP/HSR) (6GK5204-0BS00-3PA3)cisa_csaf_ot
Deactivate the webserver if not required, and if deactivation is supported by the product

cvss

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

7.8

010

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

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Csecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondaryexploitability 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:H/E:P/RL:O/RC:Csecondary · Siemens ProductCERT DE

v3.17.1highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Psecondary · CVSS-BT (t0sche)

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:Csecondary · 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

ssvc

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

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

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-399USprimaryCWE-399USCWE-399USCWE-400USCWE-401US

exploits (1)

Public proof-of-concept and weaponised exploit code.

dag-erling/kexkillProof of concept for CVE-2016-8858PoC · poc_in_github

affected products (30)

Products and version ranges known to be affected.

Dell NetWorker virtualall versionscert_bundDEcpe:/a:dell:networker:virtual
EMC Avamarall versionscert_bundDEcpe:/a:emc:avamar:-
IBM AIXall versionscert_bundDEcpe:/o:ibm:aix:-
IBM VIOSall versionscert_bundDEcpe:/a:ibm:vios:-
NetApp Data ONTAPall versionscert_bundDEcpe:/a:netapp:data_ontap:-
Open Source OpenSSHall versionscert_bundDEcpe:/a:openbsd:openssh:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
SCALANCE X204RNA (HSR) (6GK5204-0BA00-2MB2)all versionscisa_csaf_otUS
SCALANCE X204RNA (PRP) (6GK5204-0BA00-2KB2)all versionscisa_csaf_otUS
SCALANCE X204RNA EEC (HSR) (6GK5204-0BS00-2NA3)all versionscisa_csaf_otUS
SCALANCE X204RNA EEC (PRP) (6GK5204-0BS00-3LA3)all versionscisa_csaf_otUS
SCALANCE X204RNA EEC (PRP/HSR) (6GK5204-0BS00-3PA3)all versionscisa_csaf_otUS
Siemens SCALANCE X204RNA (HSR) (6GK5204-0BA00-2MB2)< V3.2.7cisa_csaf_otUS
Siemens SCALANCE X204RNA (PRP) (6GK5204-0BA00-2KB2)< V3.2.7cisa_csaf_otUS
Siemens SCALANCE X204RNA EEC (HSR) (6GK5204-0BS00-2NA3)< V3.2.7cisa_csaf_otUS
Siemens SCALANCE X204RNA EEC (PRP) (6GK5204-0BS00-3LA3)< V3.2.7cisa_csaf_otUS
Siemens SCALANCE X204RNA EEC (PRP/HSR) (6GK5204-0BS00-3PA3)< V3.2.7cisa_csaf_otUS
n/a n/a≤ n/aenisa_euvdEU
The OpenBSD Project OpenSSH≤ 7.3fstec_bduRU
openbsd openssh= 6.8nvdUScpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*

showing 20 of 30

advisories (3)

Vendor and ecosystem advisories describing this.

SSA-412672SSA-412672: Multiple OpenSSL and OpenSSH Vulnerabilities in SCALANCE X-200RNA Switch Devices before V3.2.72022-12-13csaf · siemens_psirtDE
SCALANCE X-200RNA switch devices before V3.2.7 contain multiple OpenSSL and OpenSSH vulnerabilities. The most severe of these vulnerabilities could allow a denial of service condition or could lead to execution of arbitrary code. Siemens has released updates for the affected products and recommends to update to the latest versions.
WID-SEC-W-2024-1052OpenSSH: Schwachstelle ermöglicht Denial of ServiceDeutsch2016-10-19csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in OpenSSH ausnutzen, um einen Denial of Service Angriff durchzuführen.
ICSA-22-349-21Siemens SCALANCE X-200RNA Switch Devices2022-12-13icsa · cisa_csaf_otUS
SCALANCE X-200RNA switch devices before V3.2.7 contain multiple OpenSSL and OpenSSH vulnerabilities. The most severe of these vulnerabilities could allow a denial of service condition or could lead to execution of arbitrary code. Siemens has released updates for the affected products and recommends to update to the latest versions.

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund cisa_csaf_ot nvd siemens_psirt NVD CVE.org MITRE

published 2016-12-09modified 2026-06-17

related (3,726)

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+3721 more

references (46)

External citations — patches, advisories, analysis.

scry

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