CVE-2026-20251
Remote Code Execution through Deserialization of Untrusted Data in Splunk Secure Gateway
Exploitation likely. EPSS gives it a 32% chance of exploitation in the next 30 days. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
In Splunk Enterprise versions below 10.2.4, 10.0.7, 9.4.12, and 9.3.13, Splunk Cloud Platform versions below 10.3.2512.12, 10.2.2510.14, 10.1.2507.22, and 9.3.2411.132, and Splunk Secure Gateway versions below 3.10.6, 3.9.20, and 3.8.67, a low-privileged user that does not hold the 'admin' or 'power' Splunk roles could perform a Remote Code Execution (RCE) through the Splunk Secure Gateway app.<br><br>The Remote Code Execution is possible because of unsafe deserialization of App Key Value Store (KV Store) data through the ‘jsonpickle’ Python library, which reconstructs arbitrary Python objects from specially crafted JavaScript Object Notation (JSON) without adequate validation.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
32% chance of exploitation activity in the next 30 days, which ranks it in the 98th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
8 events over 44 days, from the signal feeds we watch.
- EPSS band change0 → moderateepss band change
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Scored 8.8 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required LowRequires basic user-level privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
References in the record
In the news
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