How severe is CVE-2016-8638?

CVE-2016-8638 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2016-8638 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-8638?

CVE-2016-8638 primarily affects Ipsilon Project Ipsilon. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-8638?

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-2016-8638 published?

CVE-2016-8638 was published on 2017-07-12 and last updated on 2026-06-17.

CVE-2016-8638

CVE-2016-8638 is a critical-severity vulnerability in Ipsilon Project Ipsilon with a CVSS 3.x base score of 9.1. 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-384.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v2: 6.4
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-384
Affected product: Ipsilon Project Ipsilon
Published: 2017-07-12
Last modified: 2026-06-17

Description

A vulnerability in ipsilon 2.0 before 2.0.2, 1.2 before 1.2.1, 1.1 before 1.1.2, and 1.0 before 1.0.3 was found that allows attacker to log out active sessions of other users. This issue is related to how it tracks sessions, and allows an unauthenticated attacker to view and terminate active sessions from other users. It is also called a "SAML2 multi-session vulnerability."

Frequently asked questions

What is CVE-2016-8638?: A vulnerability in ipsilon 2.0 before 2.0.2, 1.2 before 1.2.1, 1.1 before 1.1.2, and 1.0 before 1.0.3 was found that allows attacker to log out active sessions of other users. This issue is related to how it tracks sessions, and allows an unauthenticated attacker to view and terminate active sessions from other users. It is also called a "SAML2 multi-session vulnerability."
How severe is CVE-2016-8638?: CVE-2016-8638 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2016-8638 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-8638?: CVE-2016-8638 primarily affects Ipsilon Project Ipsilon. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-8638?: 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-2016-8638 published?: CVE-2016-8638 was published on 2017-07-12 and last updated on 2026-06-17.

References

Affected products (8)

cpe:2.3:a:ipsilon_project:ipsilon:1.0.0:*:*:*:*:*:*:*
cpe:2.3:a:ipsilon_project:ipsilon:1.0.1:*:*:*:*:*:*:*
cpe:2.3:a:ipsilon_project:ipsilon:1.0.2:*:*:*:*:*:*:*
cpe:2.3:a:ipsilon_project:ipsilon:1.1.0:*:*:*:*:*:*:*
cpe:2.3:a:ipsilon_project:ipsilon:1.1.1:*:*:*:*:*:*:*
cpe:2.3:a:ipsilon_project:ipsilon:1.2.0:*:*:*:*:*:*:*
cpe:2.3:a:ipsilon_project:ipsilon:2.0.0:*:*:*:*:*:*:*
cpe:2.3:a:ipsilon_project:ipsilon:2.0.1:*:*:*:*:*:*:*

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