CVE-2026-8670

Critical

Description

Insufficient session expiration vulnerability in syslink software AG Avantra on Linux, Windows allows Reusing Session IDs (aka Session Replay). This issue affects Avantra: before 25.3.1.

SeverityCritical

CVSS9.6

Exploit probability—

ProductAvantra

PublishedMay 22, 2026

First seenMay 22, 2026

Weakness typeCWE-613CWE-613

How to fix

Update

avantra avantra25.3.1 or later

Vendor advisories

support.avantra.com/hc/en-us/articles/5533929912351

Affected products

Product	Affected versions	Fixed in
avantra avantra	v < 25.3.1	25.3.1

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

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