CVE-2018-7711 SimpleSAMLphp saml2 incorrect signature validation

What is CVE-2018-7711?

CVE-2018-7711 is a high-severity vulnerability in Debian Debian Linux, published on 5 Mar 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

HTTPRedirect.php in the saml2 library in SimpleSAMLphp before 1.15.4 has an incorrect check of return values in the signature validation utilities, allowing an attacker to get invalid signatures accepted as valid by forcing an error during validation. This occurs because of a dependency on PHP functionality that interprets a -1 error code as a true boolean value.

Weakness: CWE-347

Which versions are affected by CVE-2018-7711?

6 open source packages ship an affected version, including simplesamlphp/saml2. It affects 3 products.

Products include Debian Debian Linux, Simplesamlphp Saml2, Simplesamlphp Simplesamlphp.

How do I fix CVE-2018-7711?

Upgrade simplesamlphp/saml2 to a fixed version for your release line: 1.10.6, 2.3.8 or 3.1.4.

Is CVE-2018-7711 being exploited?

There is no known exploitation of CVE-2018-7711 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2018-7711, DLA-1314-1, GHSA-g888-g2pp-82hf, UBUNTU-CVE-2018-7711.