Splunk Enterprise Missing Authentication for Critical Function Vulnerability
Splunk · Enterprise
Splunk Enterprise (versions 10.2 below 10.2.4 and 10.0 below 10.0.7) has a missing authentication flaw in its PostgreSQL sidecar service endpoint, which lacks access controls on file operations. An attacker with network access to that endpoint can create or truncate arbitrary files without any credentials, requiring no user interaction or special configuration.
In Splunk Enterprise 10.2 versions below 10.2.4 and 10 versions below 10.0.7, an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint. The vulnerability exists because the PostgreSQL sidecar service endpoint lacks authentication controls, allowing any network-reachable user to invoke file operations without credentials. Splunk Enterprise versions 9.4 and earlier are not affected. If you cannot immediately upgrade to a fixed version, you can mitigate this vulnerability by disabling the PostgreSQL sidecar service.
- Exploited
- Yes, in CISA KEV
- Reports
- 0
- Tactics
- 2/15
How an attack unfolds
Based on MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. mappings. Select a step to see the evidence.Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
First seen exploited 5 days after disclosure. Public exploit code (PoC-in-GitHub) appeared 2 days after disclosure.
- Disclosedday 0
- Public exploit codePoC-in-GitHub+2 days
- First seen exploitedVulnCheck KEV evidence+5 days
- Added to CISA KEVEU database agrees+8 days
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
2 TechniqueOne specific attacker behaviour in MITRE ATT&CK, such as T1190 “Exploit Public-Facing Application”. IDs with a dot, like T1059.004, are sub-techniques., grouped by TacticThe attacker’s goal at a stage of an attack in MITRE ATT&CK, such as Initial Access or Persistence. Each technique belongs to one or more tactics. in kill-chain order, 2 cited passages 2Initial AccessTA0001
unauthenticated network endpoint exposed to attackers
an unauthenticated user could create or truncate arbitrary files through a PostgreSQL sidecar service endpoint
ImpactTA0040
file creation/truncation alters stored data
could create or truncate arbitrary files
Detection
0 rules for this CVE · 155 general rules for its techniquesRules for this CVE
0Sigma ruleAn open, vendor-neutral detection rule for log data. Security teams convert Sigma rules into searches for their own SIEM. that reference CVE-2026-20253 directly.CVE-specific rules are not available in this build. Search SigmaHQ ↗
General rules for this CVE’s techniques
These detect the technique in general, not this specific vulnerability.
Exploit Public-Facing ApplicationT1190149 general rules
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- CVE-2020-5902 F5 BIG-IP Exploitation Attemptcriticaltest
Stored Data ManipulationT1565.0016 general rules
Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.
What security researchers reported
Not named in any threat report yetAlso mentioned in 50 community threat pulses (AlienVault OTX)
Weaker evidencePulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.
- Actively_Exploited_Kev | Oct 31, 202630 Oct 2026
- Actively_Exploited_Kev | Oct 30, 202629 Oct 2026
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- Node2Shell / HTTP2Shell Vulnerability May Allow RCE28 Oct 2026
- Node2Shell / HTTP2Shell Vulnerability May Allow RCE28 Oct 2026
- Actively_Exploited_Kev | Oct 29, 202628 Oct 2026
- 44 more on OTX