How severe is CVE-2017-18106?

CVE-2017-18106 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2017-18106 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-18106?

CVE-2017-18106 affects Atlassian Crowd. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-18106?

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-2017-18106 published?

CVE-2017-18106 was published on 2019-03-29 and last updated on 2026-06-17.

CVE-2017-18106

CVE-2017-18106 is a high-severity vulnerability in Atlassian Crowd 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-287.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 6.0
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Atlassian Crowd
Published: 2019-03-29
Last modified: 2026-06-17

Description

The identifier_hash for a session token in Atlassian Crowd before version 2.9.1 could potentially collide with an identifier_hash for another user or a user in a different directory, this allows remote attackers who can authenticate to Crowd or an application using Crowd for authentication to gain access to another user's session provided they can make their identifier hash collide with another user's session identifier hash.

Frequently asked questions

What is CVE-2017-18106?: The identifier_hash for a session token in Atlassian Crowd before version 2.9.1 could potentially collide with an identifier_hash for another user or a user in a different directory, this allows remote attackers who can authenticate to Crowd or an application using Crowd for authentication to gain access to another user's session provided they can make their identifier hash collide with another user's session identifier hash.
How severe is CVE-2017-18106?: CVE-2017-18106 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2017-18106 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-18106?: CVE-2017-18106 affects Atlassian Crowd. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-18106?: 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-2017-18106 published?: CVE-2017-18106 was published on 2019-03-29 and last updated on 2026-06-17.

References

https://jira.atlassian.com/browse/CWD-5061

Affected products (1)

cpe:2.3:a:atlassian:crowd:*:*:*:*:*:*:*:*

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