CVE-2026-55549: Yamcs: Reflected XSS in the URL of the Authorize Endpoint
Affected: yamcs · Exploitation: check available, not yet exploited
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 71% of scored CVEs
DescriptionCVE.org
Yamcs is a mission control framework. Prior to 5.9.4, Yamcs reflects an attacker-controlled redirect_uri parameter from GET /auth/authorize into yamcs-core/src/main/resources/auth/templates/authorize.html without adequate HTML escaping by yamcs-core/src/main/java/org/yamcs/http/auth/AuthHandler.java and yamcs-core/src/main/java/org/yamcs/http/HandlerContext.java. A crafted authorization URL can execute JavaScript when opened by a Yamcs user. The script can access browser-held authentication material and transmit it to an attacker, enabling account compromise. This issue is fixed in version 5.9.4.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- yamcs · yamcs< 5.9.4
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Check available, not yet exploited. A public nuclei template can confirm it on a system you are authorised to test.
- CISA KEV
- Not listed
- Public check
- Yamcs <=5.8.6 - Cross-Site Scripting · nuclei template in projectdiscovery/nuclei-templates
- Weakness
- Cross-site Scripting
- Vendor
- yamcs
- Published
- August 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-55549 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.