CVE-2018-7644
The XmlSecLibs library as used in the saml2 library in SimpleSAMLphp before 1.15.3 incorrectly verifies signatures on SAML assertions, allowing a remote attacker to construct a crafted SAML assertion on behalf of an Identity Provider that would pass as…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.25%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
The XmlSecLibs library as used in the saml2 library in SimpleSAMLphp before 1.15.3 incorrectly verifies signatures on SAML assertions, allowing a remote attacker to construct a crafted SAML assertion on behalf of an Identity Provider that would pass as cryptographically valid, thereby allowing them to impersonate a user from that Identity Provider, aka a key confusion issue.
- CVSS 3.0
- 7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 1.25% probability · 69th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-347
- Affected
- simplesamlphp/simplesamlphp
- Source
- cve@mitre.org
EPSS 1.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://simplesamlphp.org/security/201802-01Vendor Advisory
- https://simplesamlphp.org/security/201802-01Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.