How severe is CVE-2018-7644?

CVE-2018-7644 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2018-7644 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-7644?

CVE-2018-7644 affects Simplesamlphp. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-7644?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-7644 published?

CVE-2018-7644 was published on 2018-03-05 and last updated on 2026-06-17.

CVE-2018-7644

CVE-2018-7644 is a high-severity vulnerability in Simplesamlphp with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-347.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Affected product: Simplesamlphp
Published: 2018-03-05
Last modified: 2026-06-17

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.

Frequently asked questions

What is 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 cryptographically valid, thereby allowing them to impersonate a user from that Identity Provider, aka a key confusion issue.
How severe is CVE-2018-7644?: CVE-2018-7644 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2018-7644 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-7644?: CVE-2018-7644 affects Simplesamlphp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-7644?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-7644 published?: CVE-2018-7644 was published on 2018-03-05 and last updated on 2026-06-17.

References

https://simplesamlphp.org/security/201802-01

Affected products (1)

cpe:2.3:a:simplesamlphp:simplesamlphp:*:*:*:*:*:*:*:*

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