CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Called exploited 80 days after disclosure.
Measured from the CVE publication date to the earliest of 1 KEV catalogue that list it.
The life of this vulnerability
- CVE published
- First KEV listing3mo
- Last sightingsame day
Gaps are compressed to equal steps. The elapsed time is printed under each.
Which catalogues call it exploited
- CISA KEVUS federaldoes not list it
- EUVDENISA, European Uniondoes not list it
- VulnCheck KEVcommercial researchlisted Oct 1, 2026
- CIRCLaggregator, mirrors the abovelisted Oct 5, 2026, not counted
This rests on a single catalogue. No second catalogue corroborates the claim that it is being exploited. CIRCL is an aggregator and is not counted.
Public exploitation evidence
- reported exploitationapi.vulncheck.com/v3/index/vulncheck-canaries?cve=CVE-2026-6
1 public report collected from VulnCheck and CIRCL, first on Oct 1, 2026. Each links to its original source. We have not verified them.
Description
Rejetto HFS 3.0.0 through 3.2.0 derives its session-cookie signing key from the non-cryptographic Math.random() generator and discloses outputs of the same generator to unauthenticated clients during login. A remote attacker can collect a small number of login responses, reconstruct the generator's state, recover the signing key, and forge a valid administrator session cookie, leading to full administrative access and remote code execution via the server_code configuration feature.
