CVE-2026-103636

waiting for further signalsZero needs more public information before it can validate it.

GHSA-9935-w26g-xf2m ↗EUVD-2026-96309 ↗

no check availablenot proven exploitable
cve.orgpublic pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).kevAttacks confirmed in the real world.
Apache Software Foundation Apache DataSketches >= 2.0.0-incubating, <= 5.2.0
CWE-125 Out-of-bounds Read
ETK-2026-2167Zero's internal tracking ID, independent of the CVE number., permanent identifier
20h 12msince last run
16mAI analysisAnalysis: how long the AI spent reversing this signal.
timeline
0 = cve.org publication
trigger signal (cve.org) +0hwaiting for further signals+241h49m
0
+2h
+4h
+6h
+8h
+10h

description

Apache DataSketches C++ versions 2.0.0-incubating through 5.2.0 can read beyond supplied input while decoding malformed VarOpt union data. An attacker able to provide such serialized data to an application may cause a crash or disclose adjacent process memory.

mitigation

Upgrade apache/datasketches-cpp to version 5.3.0 or later. Until upgraded, do not deserialize VarOpt union data from untrusted sources.

check
no
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.
contextual
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.
0.52%43rd percentile
agent run time
16m
cve.org record, t = 0The moment cve.org publishes the CVE in full.
2026-10-10 10:23Z
Δ to public pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).
–
Δ to kevAttacks confirmed in the real world.
–

outcome

Contextual: an exploit technique exists, but no deterministic check could cover this one.

source signals

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

  1. 2026-10-10 10:23Z
    cve_org: trigger signal, started the run

this entry in the feed

GET /api/v1/feed/CVE-2026-103636

{
  "etk_id": "ETK-2026-2167",
  "cve_id": "CVE-2026-103636",
  "display_id": "CVE-2026-103636",
  "ghsa_id": "GHSA-9935-w26g-xf2m",
  "euvd_id": "EUVD-2026-96309",
  "status": "published",
  "anchor_state": "anchored",
  "title": "Out-of-bounds read in DataSketches C++ VarOpt union deserialization",
  "summary": "Apache DataSketches C++ versions 2.0.0-incubating through 5.2.0 can read beyond supplied input while decoding malformed VarOpt union data. An attacker able to provide such serialized data to an application may cause a crash or disclose adjacent process memory.",
  "mitigation": "Upgrade apache/datasketches-cpp to version 5.3.0 or later. Until upgraded, do not deserialize VarOpt union data from untrusted sources.",
  "vendor": "Apache Software Foundation",
  "product": "Apache DataSketches",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        ">= 2.0.0-incubating, <= 5.2.0"
      ],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "apache/datasketches-cpp",
      "purl": null
    }
  ],
  "cwes": [
    125
  ],
  "cvss_score": 7.5,
  "cvss_src": "cna_vendor",
  "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
  "epss_score": 0.0052,
  "epss_percentile": 0.4331,
  "epss_asof": "2026-10-20",
  "automation": "contextual",
  "check": false,
  "check_confidence_basis": null,
  "exploit": false,
  "pipeline_minutes": 15.6096275,
  "t0_at": "2026-10-10T10:23:58.547000+00:00",
  "signals": {
    "trigger_signal": {
      "at": "2026-10-10T10:23:58.547000+00:00",
      "days": 0,
      "is_lower_bound": false,
      "measured_at": "2026-10-10T10:23:58.547000+00:00",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-103636"
    }
  }
}

published 2026-10-20 11:56Z
last change 2026-10-21 08:08Z

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