VulnTideExploited vulnerabilities, by vendor. Data as of .
Not in CISA KEVPublished CVSS 9.3 criticalEPSS 1.9% probability of exploitation in 30 daysFound by AI: Anthropic (Claude)
Rejetto

CVE-2026-61500: Rejetto HFS < 3.2.1 Session Forgery via Predictable Signing Key

Is it exploited?

Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.

How likely is exploitation in the next 30 days?
1.9%

Up from 1% on .

EPSS score, percentile 79.7 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?
9.3 Critical

CVSS v4.0 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

Advisories and patches (1)

Which versions are affected?

Affected

  • from 3.0.0 to before 3.2.1

Versions by product

Source: CISA KEV 2026.10.29, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.

What to do

Advisories and patches

This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

As listed in the CVE record.

rejetto hfs
StatusVersions
Affectedfrom 3.0.0 to before 3.2.1

Versions not listed are: affected.

Source: CVE List, as of . About the data.

About this vulnerability

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 adm…

Summary: CVE record, as of .

  • CISA has not added CVE-2026-61500 to its Known Exploited Vulnerabilities (KEV) catalog, as of 29 Oct 2026.
  • The CVE record was published on 13 Jul 2026.
  • The CVE record carries a CVSS v4.0 base score of 9.3 (Critical), given by its CNA.
  • FIRST's EPSS model puts the probability of exploitation in the next 30 days at 1.9% (percentile 79.7), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
  • CISA's SSVC assessment in the CVE record: exploitation none, automatable yes, technical impact total.
  • The credits in the CVE record name Anthropic (Claude) as finder.

Source: CISA KEV 2026.10.29, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.

Description

Rejetto HFS < 3.2.1 Session Forgery via Predictable Signing Key

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.

Source: CVE List, as of . About the data.

Weakness

CWE-338

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.

Timeline

DateEvent
CVE record published
CVE record last updated

References

1

Known exploited Rejetto vulnerabilities

  • CVE-2024-23692: Rejetto HTTP File Server Improper Neutralization of Special Elements Used in a Template Engine Vulnerability (added )
  • CVE-2014-6287: Rejetto HTTP File Server (HFS) Remote Code Execution Vulnerability (added )