How severe is CVE-2017-12870?

CVE-2017-12870 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2017-12870 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-12870?

CVE-2017-12870 affects Simplesamlphp. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-12870?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2017-12870 published?

CVE-2017-12870 was published on 2017-09-01 and last updated on 2026-06-17.

CVE-2017-12870

CVE-2017-12870 is a medium-severity vulnerability in Simplesamlphp with a CVSS 3.x base score of 5.9. 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-200.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Simplesamlphp
Published: 2017-09-01
Last modified: 2026-06-17

Description

SimpleSAMLphp 1.14.12 and earlier make it easier for man-in-the-middle attackers to obtain sensitive information by leveraging use of the aesEncrypt and aesDecrypt methods in the SimpleSAML/Utils/Crypto class to protect session identifiers in replies to non-HTTPS service providers.

Frequently asked questions

What is CVE-2017-12870?: SimpleSAMLphp 1.14.12 and earlier make it easier for man-in-the-middle attackers to obtain sensitive information by leveraging use of the aesEncrypt and aesDecrypt methods in the SimpleSAML/Utils/Crypto class to protect session identifiers in replies to non-HTTPS service providers.
How severe is CVE-2017-12870?: CVE-2017-12870 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2017-12870 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-12870?: CVE-2017-12870 affects Simplesamlphp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-12870?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-12870 published?: CVE-2017-12870 was published on 2017-09-01 and last updated on 2026-06-17.

References

https://simplesamlphp.org/security/201704-01

Affected products (1)

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

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