CVE-2026-61500

validatedZero produced an exploit or a check.

GHSA-xxrm-3f86-v97j ↗EUVD-2026-43505 ↗

check availableZero validated a working check for it.not proven exploitableZero has a detection check, but hasn't produced a full working exploit yet.
cve.orgpublic pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).+75dkevAttacks confirmed in the real world.+80d
rejetto http_file_server >= 3.0.0, < 3.2.1
fixed in 3.2.1
CWE-338 Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)
ETK-2026-540, permanent identifier
+83dTTV
47mAI analysisAnalysis: how long the AI spent reversing this signal.
Check if you are vulnerable
timeline
0 = trigger signal
cve.org publication−2.6mopublic poc−0.1motrigger signal +0mokev+0.0mocheck available+0.1moagent stopped
−2mo
−1mo

description

Rejetto HFS 3.0.0 through 3.2.0 uses predictable randomness for its session-cookie signing key. A remote attacker able to access the unauthenticated login flow may forge an administrator session and execute code through server configuration.

mitigation

Upgrade HFS to version 3.2.1 or later. Until upgraded, restrict access to the login interface to trusted networks.

fixed in 3.2.1

check
available
exploit
no
automationDeterministic: a check that runs on its own, the same request on every target. Contextual: an agentic technique that needs to be applied per target, for bugs that depend on contextual flows.
deterministic
auth requiredWhether an attacker needs an account first, based on the CVSS vector's Privileges Required.
no
EPSSEstimate of the chance this CVE is exploited in the next 30 days. Refreshed daily.
0.99%61st percentile
agent run time
47m
cve.org record, t = 0The moment cve.org publishes the CVE in full.
2026-07-13 17:21Z
Δ to public pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).
+75d
Δ to kevAttacks confirmed in the real world.
+80d

outcome

Check only, differential: the check fires on the vulnerable build and is silent on the patched one.

source signals

Public signals that triggered or updated the pipeline. These are inputs for the deltas above.

  1. 2026-07-13 17:21Z
  2. 2026-10-01
    vulncheck_kev: trigger signal, started the run
  3. 2026-10-01 00:00Z
  4. 2026-10-04 06:52Z
  5. 2026-10-05 08:09Z
    Attackers Target Rejetto HFS Flaw That Enables Admin Session Forgery and RCE
  6. 2026-10-07 08:07Z
    Anthropic Expands Claude Access for Vetted Cyber Teams as Glasswing Finds 129,000 Flaws

this entry in the feed

GET /api/v1/feed/CVE-2026-61500

{
  "etk_id": "ETK-2026-540",
  "cve_id": "CVE-2026-61500",
  "display_id": "CVE-2026-61500",
  "ghsa_id": "GHSA-xxrm-3f86-v97j",
  "euvd_id": "EUVD-2026-43505",
  "status": "published",
  "anchor_state": "anchored",
  "title": "Predictable session signing key in Rejetto HFS",
  "summary": "Rejetto HFS 3.0.0 through 3.2.0 uses predictable randomness for its session-cookie signing key. A remote attacker able to access the unauthenticated login flow may forge an administrator session and execute code through server configuration.",
  "mitigation": "Upgrade HFS to version 3.2.1 or later. Until upgraded, restrict access to the login interface to trusted networks.",
  "vendor": "rejetto",
  "product": "http_file_server",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        ">= 3.0.0, < 3.2.1"
      ],
      "ecosystem": null,
      "fixed_versions": [
        "3.2.1"
      ],
      "package_name": "hfs",
      "purl": null
    }
  ],
  "cwes": [
    338
  ],
  "cvss_score": 9.8,
  "cvss_src": "nvd",
  "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
  "epss_score": 0.0099,
  "epss_percentile": 0.6183,
  "epss_asof": "2026-10-20",
  "automation": "deterministic",
  "check": true,
  "check_confidence_basis": "differential",
  "exploit": false,
  "pipeline_minutes": 46.92906803333333,
  "t0_at": "2026-07-13T17:21:55.747000+00:00",
  "signals": {
    "check": {
      "at": "2026-10-04T08:40:53.775354+00:00",
      "days": 82.63817162446759,
      "is_lower_bound": false,
      "measured_at": "2026-07-13T17:21:55.747000+00:00",
      "url": null
    },
    "kev": {
      "at": "2026-10-01T00:00:00+00:00",
      "days": 80,
      "is_lower_bound": false,
      "measured_at": "2026-07-13T17:21:55.747000+00:00",
      "precision": "day",
      "url": "https://vulncheck.com/cve/CVE-2026-61500"
    },
    "public_poc": {
      "at": "2026-09-26T15:23:41+00:00",
      "days": 74.91788487268518,
      "is_lower_bound": false,
      "measured_at": "2026-07-13T17:21:55.747000+00:00",
      "url": "https://github.com/aramosf/CVE-2026-61500"
    },
    "trigger_signal": {
      "at": "2026-10-01T00:00:00+00:00",
      "days": 79.27643811342593,
      "is_lower_bound": false,
      "measured_at": "2026-07-13T17:21:55.747000+00:00",
      "url": "https://vulncheck.com/cve/CVE-2026-61500"
    }
  }
}

published 2026-10-04 06:39Z
last change 2026-10-21 09:43Z

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