CVE-2017-18106: atlassian crowd Improper Authentication
Vulnerability summary
CVE-2017-18106 is a high (CVSS 7.5) Improper Authentication vulnerability in atlassian crowd. EPSS estimates a 1.23% chance of exploitation in the next 30 days, higher than 69% of scored vulnerabilities.
Not severe (CVSS 7.5, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Timeline
- 29-03-2019PublishedVulnerability first disclosed.
- 16-09-2024Last modifiedVulnerability information updated.
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.
CVSS metrics
2 scores · 1 source · 2 versionsEPSS trend
Probability
1.23%
Chance of exploitation in the next 30 days
Percentile
69%
Versus all other CVEs
30-day change
No change 0.00 pp
From 1.23% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Atlassian1 product
- crowd≥ unspecified, < 2.9.1 | < 2.9.1
1 vendor · 1 product