CVE-2023-40593 | Denial of Service (DoS) in Splunk Enterprise Using a Malformed SAML Request

In Splunk Enterprise versions lower than 9.0.6 and 8.2.12, a malicious actor can send a malformed security assertion markup language (SAML) request to the `/saml/acs` REST endpoint which can cause a denial of service through a crash or hang of the Splunk daemon.

Published: 2023-08-30 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-40593 is rated Low Risk (38.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.49%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-40593

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.16% 0.49% +0.33%
2 2026-05-25 0.13% 0.16% +0.03%
3 2026-04-08 0.13%

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-40593

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 4.0 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2023-40593

Affected software / configurations for CVE-2023-40593

Vendor Product Version Raw CPE
splunk splunk >= 8.2.0, < 8.2.12 cpe:2.3:a:splunk:splunk:*:*:*:*:enterprise:*:*:*
splunk splunk >= 9.0.0, < 9.0.6 cpe:2.3:a:splunk:splunk:*:*:*:*:enterprise:*:*:*
splunk splunk_cloud_platform <= 9.0.2305.100 cpe:2.3:a:splunk:splunk_cloud_platform:*:*:*:*:*:*:*:*

References for CVE-2023-40593

cvelogic Threat Intelligence