CVE-2023-48703 — go-saml
HIGHCVE-2023-48703 is a high-severity (CVSS 7.5) Improper Authentication vulnerability in github.com/RobotsAndPencils/go-saml. The records list no fixed version yet; check the vendor advisory below and apply the mitigations in the meantime.
RobotsAndPencils go-saml authentication bypass vulnerability
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-48703.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
github.com/RobotsAndPencils/go-samlReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
RobotsAndPencils go-saml, a SAML client library written in Go, contains an authentication bypass vulnerability in all known versions. This is due to how the xmlsec1 command line tool is called internally to verify the signature of SAML assertions. When xmlsec1 is used without defining the enabled key data, the origin of the public key for the signature verification is, unfortunately, not restricted. That means an attacker can sign the SAML assertions themselves and provide the required public key (e.g. an RSA key) directly embedded in the SAML token. Projects still using RobotsAndPencils/go-saml should move to another SAML library or alternatively remove support for SAML from their projects. The vulnerability can likely temporarily be fixed by forking the go-saml project and adding the command line argument --enabled-key-data and specifying a value such as x509 or raw-x509-cert when calling the xmlsec1 binary in the verify function. Please note that this workaround must be carefully tested before it can be used.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/RobotsAndPencils/go-saml | all versions | No fix |
Affected Products
go-samlrobotsandpencilsDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/RobotsAndPencils/go-saml, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
The records we use list no patched version of github.com/RobotsAndPencils/go-saml for CVE-2023-48703. Check the maintainer's advisory, and where your build allows, override or pin the dependency away from the vulnerable range.
Mitigate without a patch
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is CVE-2023-48703 in your dependencies?
Find it across Go, including transitive dependencies.