Vulnerability · Published Sep 9, 2026 · Assigned by GitHub_M
CVE-2026-64857tirreno has Session Fixation in Login Authentication
Medium 5.3
In plain English
A medium-severity session fixation in tirreno from tirrenotechnologies. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 41% of all known vulnerabilities).
Official description
tirreno, a security framework, has a session fixation issue in versions prior to 0.10.0. During authentication, tirreno validates the user's credentials and establishes the authenticated session, but it does not call `session_regenerate_id()` afterward. As a result, the session identifier is not rotated on login, it stays the same before and after authentication. An attacker able to fix a known session identifier in a victim's browser (for example through a network man-in-the-middle position, or a separate cross-site scripting or subdomain cookie-injection issue) could then gain access to the victim's authenticated session. The issue is fixed in v0.10.0. The session identifier is now regenerated on successful authentication, and the previous session is destroyed. There is no configuration-level workaround.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| tirrenotechnologies | tirreno | < 0.10.0 |
Weakness: CWE-384 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N