CVE-2023-25957 [Critical] | Authentication Bypass in Saml

A vulnerability has been identified in Mendix SAML (Mendix 7 compatible) (All versions >= V1.16.4 < V1.17.3), Mendix SAML (Mendix 8 compatible) (All versions >= V2.2.0 < V2.3.0), Mendix SAML (Mendix 9 latest compatible, New Track) (All versions >= V3.1.9 < V3.3.1), Mendix SAML (Mendix 9 latest compatible, Upgrade Track) (All versions >= V3.1.8 < V3.3.0), Mendix SAML (Mendix 9.6 compatible, New Track) (All versions >= V3.1.9 < V3.2.7), Mendix SAML (Mendix 9.6 compatible, Upgrade Track) (All versions >= V3.1.8 < V3.2.6). The affected versions of the module insufficiently verify the SAML assertions. This could allow unauthenticated remote attackers to bypass authentication and get access to the application. For compatibility reasons, fix versions still contain this issue, but only when the recommended, default configuration option `'Use Encryption'` is disabled.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-03-24	0.04%	0.06%	+0.02%
2	2026-03-15	0.05%	0.04%	-0.01%
3	2026-01-10	—	0.05%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-03-24

0.04%

0.06%

+0.02%

2026-03-15

0.05%

0.04%

-0.01%

2026-01-10

—

0.05%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
9.1	3.1	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N` 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:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:N) Service keeps running; no real outage angle.	3.9	5.2	[email protected]
7.5	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N` 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:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:N) Service keeps running; no real outage angle.	3.9	3.6	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

9.1

3.1

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N 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:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N): Service keeps running; no real outage angle.

3.9

5.2

[email protected]

7.5

3.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 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:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:N): Service keeps running; no real outage angle.

3.9

3.6

[email protected]

Affected software / configurations for CVE-2023-25957

Vendor	Product	Version	Raw CPE
mendix	saml	>= 1.16.4, < 1.17.2	cpe:2.3:a:mendix:saml::::::mendix::*
mendix	saml	>= 2.2.0, < 2.2.3	cpe:2.3:a:mendix:saml::::::mendix::*
mendix	saml	>= 3.1.9, < 3.2.5	cpe:2.3:a:mendix:saml::::::mendix::*

References for CVE-2023-25957

URL	Tags
https://cert-portal.siemens.com/productcert/pdf/ssa-851884.pdf	Third Party Advisory

URL

CVE-2023-25957

Exploit prediction scoring system (EPSS) score for CVE-2023-25957

Common vulnerability scoring system (CVSS) metrics for CVE-2023-25957

Weakness enumeration for CVE-2023-25957

Affected software / configurations for CVE-2023-25957

References for CVE-2023-25957