CVE-2020-12676
FusionAuth fusionauth-samlv2 0.2.3 allows remote attackers to forge messages and bypass...
FusionAuth fusionauth-samlv2 0.2.3 allows remote attackers to forge messages and bypass authentication via a SAML assertion that lacks a Signature element, aka a "Signature exclusion attack".
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
FusionAuth fusionauth-samlv2 0.2.3 allows remote attackers to forge messages and bypass authentication via a SAML assertion that lacks a Signature element, aka a "Signature exclusion attack".
- Record
CVE-2020-12676- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - CVSS 2.0
- 6.4 Medium
AV:N/AC:L/Au:N/C:P/I:P/A:N - Weakness
- CWE-347
- Updated
- 2026-11-02
CVE List No score
FusionAuth fusionauth-samlv2 0.2.3 allows remote attackers to forge messages and bypass authentication via a SAML assertion that lacks a Signature element, aka a "Signature exclusion attack".
- Record
CVE-2020-12676- Updated
- 2026-11-02
EUVDEUVD-2020-4972 No score
FusionAuth fusionauth-samlv2 0.2.3 allows remote attackers to forge messages and bypass authentication via a SAML assertion that lacks a Signature element, aka a "Signature exclusion attack".
- Record
EUVD-2020-4972- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-qh45-328h-49g4 No score
FusionAuth fusionauth-samlv2 0.2.3 allows remote attackers to forge messages and bypass...
FusionAuth fusionauth-samlv2 0.2.3 allows remote attackers to forge messages and bypass authentication via a SAML assertion that lacks a Signature element, aka a "Signature exclusion attack".
- Record
GHSA-qh45-328h-49g4- Weakness
- CWE-347
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-12676 is a critical vulnerability (CVSS 9.1) in Fusionauth Samlv2, published October 2, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.93%, the 87th percentile. No source names a fixed version.
References
nds.ruhr-uni-bochum.de/media/nds/veroeffentlichungen/2012/08/22/BreakingSAML_3.pdf
github.com/SAMLRaider/SAMLRaider
seclists.org/fulldisclosure/2020/Oct/1
compass-security.com/fileadmin/Research/Advisories/2020-06_CSNC-2020-002_FusionAuth_Signature_Exclusion_Attack.txt
packetstormsecurity.com/files/159454/FusionAuth-SAMLv2-0.2.3-Message-Forging.html
nvd.nist.gov/vuln/detail/CVE-2020-12676