CVE Intelligence
Medium Access control

CVE-2025-20386 — Incorrect permission assignment on Splunk Enterprise for Windows during new installation or upgrade

In Splunk Enterprise for Windows versions below 10.0.2, 9.4.6, 9.3.8, and 9.2.10, a new installation of or an upgrade to an affected version can result in incorrect permissions assignment in the Splunk Enterprise for Windows Installation directory. This lets non-administrator users on the machine access the directory and all its contents.

Published Dec 3, 2025 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: cisco

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.5% (30-day exploitation probability)+6
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.49%
ahead of 41% of scored CVEs · Oct 14, 2026
Affects
Splunk
Splunk and 1 more
CVSS base
6.5
Medium · 3 source(s)
Prioritization reference: 8.0 provisional

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Splunk Splunk, Splunk Splunk Enterprise).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Search available logs for exploit probes matching the vulnerability class (access control), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Splunk Splunk ≥ 9.2.0 and < 9.2.10≥ 9.3.0 and < 9.3.8≥ 9.4.0 and < 9.4.6≥ 10.0.0 and < 10.0.2 Vulnerable NIST National Vulnerability Database
Splunk Splunk Enterprise ≥ 10.0 and < 10.0.2≥ 9.4 and < 9.4.6≥ 9.3 and < 9.3.8≥ 9.2 and < 9.2.10 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.0 CVSS 3.1 High 2.1 5.9 psirt@cisco.com via NIST National Vulnerability Database
8.0 CVSS 3.1 High — — cisco via CVE Program (cve.org) e CISA ADP
6.5 CVSS 3.1 Medium 2.8 3.6 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N (score shown at the top: nvd@nist.gov)
Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 8.0 (psirt@cisco.com via NIST National Vulnerability Database) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-732 · Incorrect Permission Assignment for Critical Resource

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.49%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Audit administrative actions and access to resources outside each user’s normal pattern.
web/proxy/WAF logsnetwork IDS/IPSauthentication logsapplication logs

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · splunk/splunk enterprise
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • CVSS changed · 6.5
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • 2025
  • CVE published
    Dec 3, 2025 · cisco

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

Elsewhere on this site

Splunk
every CVE for this vendor
Access control
same class
CWE-732
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-76285 Improper Adherence to Coding Standards in Splunk Enterprise 8d
  • CVE-2026-76284 Improper Neutralization in Splunk Enterprise 8d
  • CVE-2026-76279 Improper Input Validation of Index Names through the collect Command in Splunk Enterprise 8d
  • CVE-2026-76281 Improper Access Control in Splunk Enterprise 8d
  • CVE-2026-76280 Incorrect Permission Assignment for App Key Value Store Collections in Splunk Secure Gateway 8d
  • CVE-2026-76278 Authorization Bypass in SPL2 Module Permissions in Splunk Enterprise 8d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2025-20386 is "Incorrect permission assignment on Splunk Enterprise for Windows during new installation or upgrade", rated Medium. It affects Splunk (Splunk); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.5 describes technical severity. EPSS 0.49% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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