CVE-2018-7711
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.19%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.0
- 8.1 HIGHCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.19% probability · 68th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-347
- Affected
- simplesamlphp/simplesamlphp · simplesamlphp/saml2 · debian/debian linux
- Source
- cve@mitre.org
EPSS 1.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/simplesamlphp/saml2/commit/4f6af7f69f29df8555a18b9bb7b646906b45924dPatch
- https://lists.debian.org/debian-lts-announce/2018/03/msg00017.htmlThird Party Advisory
- https://simplesamlphp.org/security/201803-01Vendor Advisory
- https://github.com/simplesamlphp/saml2/commit/4f6af7f69f29df8555a18b9bb7b646906b45924dPatch
- https://lists.debian.org/debian-lts-announce/2018/03/msg00017.htmlThird Party Advisory
- https://simplesamlphp.org/security/201803-01Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.