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CVE-2026-61500 (GCVE-0-2026-61500)

Vulnerability from cvelistv5 – Published: 2026-07-13 17:21 – Updated: 2026-07-15 14:14 X_Open Source
VLAI
Title
Rejetto HFS < 3.2.1 Session Forgery via Predictable Signing Key
Summary
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.
Severity
9.3 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-15 14:14 UTC
CWE
  • CWE-338 - Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)
Assigner
References
Impacted products
Vendor Product Version CPE status
rejetto hfs Affected: 3.0.0 , < 3.2.1 (semver)
guessed Create a notification for this product.
Date Public
2026-07-13 00:00
Credits
Zach Hanley (@hacks_zach) of Horizon3.ai, in collaboration with Claude and Anthropic Research
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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