CVE-2026-55653

mediumpriority · track · 26EPSS 0.004 · 37 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.43% (37th) EPSS

CVSS 6.5 · medium

Is it mine?

20 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-26

A flaw was found in OpenSSH. A malicious SSH server can exploit a double free vulnerability in the Diffie-Hellman Group Exchange (DH-GEX) client path. This occurs during FIPS (Federal Information Processing Standards) mode known-group validation when the client processes attacker-controlled DH-GEX group parameters. Successful exploitation leads to client-side process termination, resulting in a Denial of Service (DoS).

cvss

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

6.5

010

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

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Lsecondary · ENISA EU

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Lsecondary · secalert@redhat.com USexploitability 2.8 · impact 1.4

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

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

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-415US

affected products (20)

Products and version ranges known to be affected.

Fedora Linuxall versionscert_bundDEcpe:/o:fedoraproject:fedora:-
IBM Security Verify Accessall versionscert_bundDEcpe:/a:ibm:security_verify_access:-
Open Source OpenSSH 9.9p1-22.el10_2all versionscert_bundDEcpe:/a:openbsd:openssh:9.9p1-22.el10_2
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
RESF Rocky Linuxall versionscert_bundDEcpe:/o:resf:rocky_linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Red Hat Red Hat Enterprise Linux 10< 0:9.9p1-25.el10_2enisa_euvdEU
Red Hat Red Hat Enterprise Linux 8< 0:8.0p1-30.el8_10enisa_euvdEU
Red Hat Red Hat Enterprise Linux 9< 0:9.9p1-9.el9_8enisa_euvdEU
Red Hat Red Hat Hardened Images< 10.3p1-6.hum1enisa_euvdEU
Red Hat Red Hat Update Infrastructure 5< 1786435483enisa_euvdEU
Red Hat Red Hat Update Infrastructure 5< 1786533529enisa_euvdEU
openbsd opensshall versionsnvdUScpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*
redhat enterprise linux= 10.0nvdUScpe:2.3:o:redhat:enterprise_linux:*:*:*:*:*:*:*:*
redhat enterprise linux= 6.0nvdUScpe:2.3:o:redhat:enterprise_linux:*:*:*:*:*:*:*:*
redhat enterprise linux= 7.0nvdUScpe:2.3:o:redhat:enterprise_linux:*:*:*:*:*:*:*:*
redhat enterprise linux= 8.0nvdUScpe:2.3:o:redhat:enterprise_linux:*:*:*:*:*:*:*:*
redhat enterprise linux= 9.0nvdUScpe:2.3:o:redhat:enterprise_linux:*:*:*:*:*:*:*:*
redhat hardened imagesall versionsnvdUScpe:2.3:a:redhat:hardened_images:*:*:*:*:*:*:*:*
redhat openshift container platform= 4.0nvdUScpe:2.3:a:redhat:openshift_container_platform:*:*:*:*:*:*:*:*

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-2039OpenSSH: Mehrere SchwachstellenDeutsch2026-06-22csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in OpenSSH ausnutzen, um einen Denial of Service Angriff durchzuführen, Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren oder vertrauliche Informationen offenzulegen.
WID-SEC-W-2026-3043IBM QRadar SIEM: Mehrere SchwachstellenDeutsch2026-08-26csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um seine Privilegien zu erhöhen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, um einen Cross-Site Scripting Angriff durchzuführen und um beliebigen Programmcode auszuführen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2026-06-23modified 2026-10-26

references (58)

External citations — patches, advisories, analysis.

scry

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