CVE-2023-45683

Cross site scripting via missing binding syntax validation In ACS location in github.com/crewjam/saml

MEDIUM
6.1
CVSS Score
Published: October 16, 2023 at 06:13 PM UTC
Updated: June 17, 2026 at 06:29 AM UTC
2 products affected across 2 vendorsSamlProject Saml

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Severity
MEDIUM6.1
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

github.com/crewjam/saml is a saml library for the go language. In affected versions the package does not validate the ACS Location URI according to the SAML binding being parsed. If abused, this flaw allows attackers to register malicious Service Providers at the IdP and inject Javascript in the ACS endpoint definition, achieving Cross-Site-Scripting (XSS) in the IdP context during the redirection at the end of a SAML SSO Flow. Consequently, an attacker may perform any authenticated action as the victim once the victim’s browser loaded the SAML IdP initiated SSO link for the malicious service provider. Note: SP registration is commonly an unrestricted operation in IdPs, hence not requiring particular permissions or publicly accessible to ease the IdP interoperability. This issue is fixed in version 0.4.14. Users unable to upgrade may perform external validation of URLs provided in SAML metadata, or restrict the ability for end-users to upload arbitrary metadata.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 0.4.14
Affected range stops below 0.4.14, so it looks safe — our inference, not a vendor statement
v < 0.4.14
Affected range stops below 0.4.14, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-79

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