How severe is CVE-2023-36661?

CVE-2023-36661 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 none, and availability high.

Is CVE-2023-36661 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-36661?

CVE-2023-36661 primarily affects Shibboleth Xmltooling. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-36661?

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-2023-36661 published?

CVE-2023-36661 was published on 2023-06-25 and last updated on 2026-06-17.

CVE-2023-36661

CVE-2023-36661 is a high-severity vulnerability in Shibboleth Xmltooling 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-918.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-918
Affected product: Shibboleth Xmltooling
Published: 2023-06-25
Last modified: 2026-06-17

Description

Shibboleth XMLTooling before 3.2.4, as used in OpenSAML and Shibboleth Service Provider, allows SSRF via a crafted KeyInfo element. (This is fixed in, for example, Shibboleth Service Provider 3.4.1.3 on Windows.)

Frequently asked questions

What is CVE-2023-36661?: Shibboleth XMLTooling before 3.2.4, as used in OpenSAML and Shibboleth Service Provider, allows SSRF via a crafted KeyInfo element. (This is fixed in, for example, Shibboleth Service Provider 3.4.1.3 on Windows.)
How severe is CVE-2023-36661?: CVE-2023-36661 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 none, and availability high.
Is CVE-2023-36661 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-36661?: CVE-2023-36661 primarily affects Shibboleth Xmltooling. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-36661?: 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-2023-36661 published?: CVE-2023-36661 was published on 2023-06-25 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:shibboleth:xmltooling:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:12.0:*:*:*:*:*:*:*

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