CVE-2020-26574

Severity: critical (CVSS 9.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.1% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2020-10-06 · updated 2026-06-17
Weakness: CWE-79

Description

Leostream Connection Broker 8.2.x is affected by stored XSS. An unauthenticated attacker can inject arbitrary JavaScript code via the webquery.pl User-Agent HTTP header. It is rendered by the admins the next time they log in. The JavaScript injected can be used to force the admin to upload a malicious Perl script that will be executed as root via libMisc::browser_client. NOTE: This vulnerability only affects products that are no longer supported by the maintainer

Affected products

Leostream Connection Broker: from 8.2.15 through 8.2.73

References

https://adepts.of0x.cc/leostream-xss-to-rce/
https://www.leostream.com/resources/product-lifecycle/
https://adepts.of0x.cc/leostream-xss-to-rce/
https://www.leostream.com/resources/product-lifecycle/

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