---
cve: "CVE-2020-5261"
severity: "HIGH"
cvss: 8.2
epss: "1.5%"
vendor: "Sustainsys"
kev: false
exploited: false
published: "2020-03-25 01:15:15"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-20T18:27:09+02:00"
---

# CVE-2020-5261

> 8.2 HIGH · 🧪 PoC

## Beschreibung

Saml2 Authentication services for ASP.NET (NuGet package Sustainsys.Saml2) greater than 2.0.0, and less than version 2.5.0 has a faulty implementation of Token Replay Detection. Token Replay Detection is an important defence in depth measure for Single Sign On solutions. The 2.5.0 version is patched. Note that version 1.0.1 is not affected. It has a correct Token Replay Implementation and is safe to use. Saml2 Authentication services for ASP.NET (NuGet package Sustainsys.Saml2) greater than 2.0.0, and less than version 2.5.0 have a faulty implementation of Token Replay Detection. Token Replay Detection is an important defense measure for Single Sign On solutions. The 2.5.0 version is patched. Note that version 1.0.1 and prior versions are not affected. These versions have a correct Token Replay Implementation and are safe to use.

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |
| S Scope | Verändert | bad |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Keine | good |

## Patch verfügbar (OSV)

- 6ddb55085dba2aeb0d990d3772e121b3815c524c (Commit)
- e58e0a1aff2b1ead6aca080b7cdced55ee6d5241 (Commit)

## Referenzen

- <https://github.com/Sustainsys/Saml2/security/advisories/GHSA-g6j2-ch25-5mmv>
- <https://github.com/Sustainsys/Saml2/commit/e58e0a1aff2b1ead6aca080b7cdced55ee6d5241>
- <https://github.com/Sustainsys/Saml2/issues/711>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2020-5261) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_
