SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2017-18122

A signature-validation bypass issue was discovered in SimpleSAMLphp through 1.14.16.

HIGH 8.1EPSS 1.08%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.08%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A signature-validation bypass issue was discovered in SimpleSAMLphp through 1.14.16. A SimpleSAMLphp Service Provider using SAML 1.1 will regard as valid any unsigned SAML response containing more than one signed assertion, provided that the signature of at least one of the assertions is valid. Attributes contained in all the assertions received will be merged and the entityID of the first assertion received will be used, allowing an attacker to impersonate any user of any IdP given an assertion signed by the targeted IdP.

CVSS 3.0
8.1 HIGHCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.08% probability · 63th percentile
CISA KEV
Not listed
Weakness
CWE-347
Affected
simplesamlphp/simplesamlphp · debian/debian linux
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.