How severe is CVE-2017-16853?

CVE-2017-16853 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2017-16853 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-16853?

CVE-2017-16853 primarily affects Shibboleth Opensaml. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-16853?

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-2017-16853 published?

CVE-2017-16853 was published on 2017-11-16 and last updated on 2026-06-17.

CVE-2017-16853

CVE-2017-16853 is a high-severity vulnerability in Shibboleth Opensaml with a CVSS 3.x base score of 8.1. 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 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Affected product: Shibboleth Opensaml
Published: 2017-11-16
Last modified: 2026-06-17

Description

The DynamicMetadataProvider class in saml/saml2/metadata/impl/DynamicMetadataProvider.cpp in OpenSAML-C in OpenSAML before 2.6.1 fails to properly configure itself with the MetadataFilter plugins and does not perform critical security checks such as signature verification, enforcement of validity periods, and other checks specific to deployments, aka CPPOST-105.

Frequently asked questions

What is CVE-2017-16853?: The DynamicMetadataProvider class in saml/saml2/metadata/impl/DynamicMetadataProvider.cpp in OpenSAML-C in OpenSAML before 2.6.1 fails to properly configure itself with the MetadataFilter plugins and does not perform critical security checks such as signature verification, enforcement of validity periods, and other checks specific to deployments, aka CPPOST-105.
How severe is CVE-2017-16853?: CVE-2017-16853 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2017-16853 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-16853?: CVE-2017-16853 primarily affects Shibboleth Opensaml. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-16853?: 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-2017-16853 published?: CVE-2017-16853 was published on 2017-11-16 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:shibboleth:opensaml:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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