Splunk Enterprise 9.3.0 < 9.3.12, 9.4.0 < 9.4.11, 10.0.0 < 10.0.6, 10.2 < 10.2.3 (SVD-2026-0505)

high Nessus Plugin ID 315749

Synopsis

An application running on a remote web server host is affected by a vulnerability

Description

The version of Splunk installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the SVD-2026-0505 advisory.

- Expr is an expression language and expression evaluation for Go. Prior to version 1.17.7, several builtin functions in Expr, including `flatten`, `min`, `max`, `mean`, and `median`, perform recursive traversal over user-provided data structures without enforcing a maximum recursion depth. If the evaluation environment contains deeply nested or cyclic data structures, these functions may recurse indefinitely until exceed the Go runtime stack limit. This results in a stack overflow panic, causing the host application to crash. While exploitability depends on whether an attacker can influence or inject cyclic or pathologically deep data into the evaluation environment, this behavior represents a denial-of-service (DoS) risk and affects overall library robustness. Instead of returning a recoverable evaluation error, the process may terminate unexpectedly. In affected versions, evaluation of expressions that invoke certain builtin functions on untrusted or insufficiently validated data structures can lead to a process- level crash due to stack exhaustion. This issue is most relevant in scenarios where Expr is used to evaluate expressions against externally supplied or dynamically constructed environments; cyclic references (directly or indirectly) can be introduced into arrays, maps, or structs; and there are no application-level safeguards preventing deeply nested input data. In typical use cases with controlled, acyclic data, the issue may not manifest. However, when present, the resulting panic can be used to reliably crash the application, constituting a denial of service. The issue has been fixed in the v1.17.7 versions of Expr. The patch introduces a maximum recursion depth limit for affected builtin functions.
When this limit is exceeded, evaluation aborts gracefully and returns a descriptive error instead of panicking. Additionally, the maximum depth can be customized by users via `builtin.MaxDepth`, allowing applications with legitimate deep structures to raise the limit in a controlled manner. Users are strongly encouraged to upgrade to the patched release, which includes both the recursion guard and comprehensive test coverage to prevent regressions. For users who cannot immediately upgrade, some mitigations are recommended. Ensure that evaluation environments cannot contain cyclic references, validate or sanitize externally supplied data structures before passing them to Expr, and/or wrap expression evaluation with panic recovery to prevent a full process crash (as a last-resort defensive measure). These workarounds reduce risk but do not fully eliminate the issue without the patch. (CVE-2025-68156)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade Splunk Enterprise to versions 10.2.3, 10.0.6, 9.4.11, 9.3.12, or higher.

See Also

https://advisory.splunk.com/advisories/SVD-2026-0505.html

Plugin Details

Severity: High

ID: 315749

File Name: splunk_1023_cve-2025-68156.nasl

Version: 1.1

Type: Combined

Agent: windows, macosx, unix

Family: CGI abuses

Published: 5/20/2026

Updated: 5/20/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

CVSS Score Source: CVE-2025-68156

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:splunk:splunk

Required KB Items: installed_sw/Splunk

Exploit Ease: No known exploits are available

Patch Publication Date: 5/20/2026

Vulnerability Publication Date: 12/16/2025

Reference Information

CVE: CVE-2025-68156