---
title: "CVE-2024-45409: SAML authentication bypass via Incorrect XPath selector"
url: https://erroneo.us/security/cve/CVE-2024-45409/
description: "CVE-2024-45409 (ruby-saml (RubyGems)): The Ruby SAML library is for implementing the client side of a SAML authorization. Ruby-SAML in"
type: vulnerability-record
section: "Security Digest"
date_published: 2024-09-10
date_modified: 2024-11-11
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2024-45409"
kev: false
cvss: 9.9
epss: 0.10684
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2024-45409: SAML authentication bypass via Incorrect XPath selector

**Signal:** High exploit likelihood. EPSS ranks it in the top 5% of all CVEs for likely exploitation in the next 30 days. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 10.7% , percentile 96: FIRST’s model estimates a 10.7% chance of exploitation activity in the next 30 days, higher than 96% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes ruby-saml (RubyGems) < 1.12.3, fixed in 1.12.3 ; ruby-saml (RubyGems) >= 1.13.0, < 1.17.0, fixed in 1.17.0 . Check your lockfile, including transitive dependencies.

## What it is

The Ruby SAML library is for implementing the client side of a SAML authorization. Ruby-SAML in

## Affected packages

- RubyGems `ruby-saml` < 1.12.3 → fixed: 1.12.3
- RubyGems `ruby-saml` >= 1.13.0, < 1.17.0 → fixed: 1.17.0

## Affected products (CVE record)

- SAML-Toolkits ruby-saml: < 1.12.3, >= 1.13.0, < 1.17.0

## Severity

- GitHub_M CVSS 3.1: 10 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N`
- GitHub CVSS 4.0: 9.9 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 10.68% probability of exploitation activity in the next 30 days; percentile 96.

## Sources

- [GitHub Advisory GHSA-jw9c-mfg7-9rx2](https://github.com/advisories/GHSA-jw9c-mfg7-9rx2)
- [CVE.org record CVE-2024-45409](https://www.cve.org/CVERecord?id=CVE-2024-45409)
- [NVD entry CVE-2024-45409](https://nvd.nist.gov/vuln/detail/CVE-2024-45409)
- [github.com](https://github.com/SAML-Toolkits/ruby-saml/security/advisories/GHSA-jw9c-mfg7-9rx2)
- [github.com](https://github.com/omniauth/omniauth-saml/security/advisories/GHSA-cvp8-5r8g-fhvq)
- [github.com](https://github.com/SAML-Toolkits/ruby-saml/commit/1ec5392bc506fe43a02dbb66b68741051c5ffeae)
- [github.com](https://github.com/SAML-Toolkits/ruby-saml/commit/4865d030cae9705ee5cdb12415c654c634093ae7)
- [ssoready.com](https://ssoready.com/blog/engineering/ruby-saml-pwned-by-xml-signature-wrapping-attacks/)
- [news.ycombinator.com](https://news.ycombinator.com/item?id=41586031)
- [security.netapp.com](https://security.netapp.com/advisory/ntap-20240926-0008/)
- [lists.debian.org](https://lists.debian.org/debian-lts-announce/2024/11/msg00006.html)
- [github.com](https://github.com/omniauth/omniauth-saml/commit/4274e9d57e65f2dcaae4aa3b2accf831494f2ddd)
- [github.com](https://github.com/rubysec/ruby-advisory-db/blob/master/gems/omniauth-saml/CVE-2024-45409.yml)
- [github.com](https://github.com/rubysec/ruby-advisory-db/blob/master/gems/ruby-saml/CVE-2024-45409.yml)
- [github.com](https://github.com/rubysec/ruby-advisory-db/blob/master/gems/omniauth-saml/GHSA-cvp8-5r8g-fhvq.yml)

---
Source page: https://erroneo.us/security/cve/CVE-2024-45409/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt