CVE-2025-27773— SimpleSAMLphp SAML2 library has incorrect signature verification for HTTP-Redirect binding
Quick assessment
Affected
simplesamlphp saml2
Exploitation
Public or AI PoC available; prioritize validation
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
SimpleSAMLphp SAML2是SimpleSAMLphp开源的一个 SAML2 PHP库。 SimpleSAMLphp SAML2 4.17.0版本和5.0.0-alpha.20版本之前版本存在数据伪造问题漏洞，该漏洞源于HTTPRedirect绑定中的签名混淆攻击，可能导致应用程序接受未签名的消息。
Possible ATT&CK Techniques 1 AI
T1190 · Exploit Public-Facing Application
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I. Basic Information for CVE-2025-27773
Vulnerability Information
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Vulnerability Title
SimpleSAMLphp SAML2 library has incorrect signature verification for HTTP-Redirect binding
Source: CVE Program / CVE List V5
Vulnerability Description
The SimpleSAMLphp SAML2 library is a PHP library for SAML2 related functionality. Prior to versions 4.17.0 and 5.0.0-alpha.20, there is a signature confusion attack in the HTTPRedirect binding. An attacker with any signed SAMLResponse via the HTTP-Redirect binding can cause the application to accept an unsigned message. Versions 4.17.0 and 5.0.0-alpha.20 contain a fix for the issue.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
密码学签名的验证不恰当
Source: CVE Program / CVE List V5
Vulnerability Title
SimpleSAMLphp SAML2 数据伪造问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
SimpleSAMLphp SAML2是SimpleSAMLphp开源的一个 SAML2 PHP库。 SimpleSAMLphp SAML2 4.17.0版本和5.0.0-alpha.20版本之前版本存在数据伪造问题漏洞，该漏洞源于HTTPRedirect绑定中的签名混淆攻击，可能导致应用程序接受未签名的消息。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| simplesamlphp | saml2 | < 4.17.0 | - |
|
II. Public POCs for CVE-2025-27773
| # | POC Description | Source Link | Shenlong Link |
|---|
AI-Generated POC
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Qwen3.6-35B-A3B
· 9169 chars
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III. Intelligence Information for CVE-2025-27773
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Patches & Fixes for CVE-2025-27773 (1)
Vendor Advisories for CVE-2025-27773 (1)
-
https://github.com/simplesamlphp/saml2/security/advisories/GHSA-46r4-f8gj-xg56 x_refsource_CONFIRM
Other References for CVE-2025-27773 (2)
IV. Related Vulnerabilities
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Same weakness: CWE-347
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V. Comments for CVE-2025-27773
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