How severe is CVE-2017-2646?

CVE-2017-2646 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2017-2646 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-2646?

CVE-2017-2646 affects Redhat Keycloak. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-2646?

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

When was CVE-2017-2646 published?

CVE-2017-2646 was published on 2018-07-27 and last updated on 2026-06-17.

CVE-2017-2646

CVE-2017-2646 is a high-severity vulnerability in Redhat Keycloak with a CVSS 3.x base score of 7.5. 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-835.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: Redhat Keycloak
Published: 2018-07-27
Last modified: 2026-06-17

Description

It was found that when Keycloak before 2.5.5 receives a Logout request with a Extensions in the middle of the request, the SAMLSloRequestParser.parse() method ends in a infinite loop. An attacker could use this flaw to conduct denial of service attacks.

Frequently asked questions

What is CVE-2017-2646?: It was found that when Keycloak before 2.5.5 receives a Logout request with a Extensions in the middle of the request, the SAMLSloRequestParser.parse() method ends in a infinite loop. An attacker could use this flaw to conduct denial of service attacks.
How severe is CVE-2017-2646?: CVE-2017-2646 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2017-2646 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-2646?: CVE-2017-2646 affects Redhat Keycloak. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-2646?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2017-2646 published?: CVE-2017-2646 was published on 2018-07-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:redhat:keycloak:*:*:*:*:*:*:*:*

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