PatchTheCVECVE-2017-2646: It was found that when Keycloak before 2.5.5 receives a Logout request with a Extensions in the middle of the
CVE-2017-2646 is a high-severity flaw (CVSS 7.5) affecting keycloak. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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.
Why this priority
- High severity
- Remotely exploitable, no login, no user action
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.5 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 1.8% (top 21%) |
| CISA exploited list | No |
| Weakness | CWE-835 |
| Published | 2018-07-27 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2017-2646?
keycloak: upgrade to 2.5.5. Exact commands for each OS are on this page.
Is CVE-2017-2646 being exploited?
CVE-2017-2646 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2017-2646 affect?
CVE-2017-2646 affects keycloak. Severity is high (CVSS 7.5). 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 ser
How urgent is CVE-2017-2646?
Priority 56/100. High severity; Remotely exploitable, no login, no user action; On your watchlist
Software pages
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