LiveActive security incident?Get immediate response
CVE Record

CVE-2018-7711: HTTPRedirect.php in the saml2 library in SimpleSAMLphp before 1.15.4 has an incorrect check of return value...

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.

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2018-7711 affects SimpleSAMLphp’s SAML2 signature validation before version 1.15.4. A logic error could let an invalid SAML signature be treated as valid when validation errors occur. For organizations relying on SimpleSAMLphp for single sign-on, this is a serious identity-trust issue, but the provided sources do not report active exploitation.

Executive priority

Prioritize remediation for internet-facing or business-critical SSO services. This vulnerability affects whether identity messages can be trusted, so the business impact could be high even without confirmed exploitation. Treat as urgent if outdated SimpleSAMLphp is in authentication paths.

Technical view

HTTPRedirect.php in the SimpleSAMLphp saml2 library incorrectly handled return values from signature validation utilities. PHP could interpret an OpenSSL -1 error as boolean true, causing failed signature verification to be accepted. The vendor fix changes validation handling. The CVE identifies SimpleSAMLphp before 1.15.4 as affected.

Likely exposure

Exposure is likely where SimpleSAMLphp versions before 1.15.4, or downstream packaged versions, process signed SAML messages using the affected saml2 library. Debian LTS published a related simplesamlphp security update. The bundle does not provide CPEs, CVSS, or a complete downstream product list.

Exploitation context

The issue requires forcing an error during signature validation so an invalid signature is accepted. In practical terms, this could undermine SAML trust decisions. The provided sources do not include public exploit details, exploitation prerequisites beyond the validation error condition, or evidence of active exploitation.

Researcher notes

Evidence is strongest for the vendor advisory, CVE description, Debian LTS advisory, and the upstream commit. No CVSS, CWE, CPE, or KEV listing is provided in the bundle. Avoid assuming affected third-party products unless they are confirmed to bundle the vulnerable saml2 code.

Mitigation direction

  • Upgrade SimpleSAMLphp to version 1.15.4 or later.
  • Apply the relevant Debian LTS simplesamlphp security update if using Debian packages.
  • Check SimpleSAMLphp vendor advisory for environment-specific guidance.
  • Inventory applications bundling or depending on the saml2 library.

Validation and detection

  • Identify all SimpleSAMLphp installations and record installed versions.
  • Confirm whether HTTPRedirect.php comes from a version before 1.15.4.
  • Check package manager history for the Debian security update where applicable.
  • Review dependency manifests for bundled SimpleSAMLphp saml2 code.
Prepared
Confidence
high
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2018-7711 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
4Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.