How severe is CVE-2015-6997?

CVE-2015-6997 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2015-6997 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-6997?

CVE-2015-6997 primarily affects Apple Iphone Os. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2015-6997?

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

When was CVE-2015-6997 published?

CVE-2015-6997 was published on 2015-10-23 and last updated on 2026-06-17.

CVE-2015-6997

CVE-2015-6997 is a medium-severity vulnerability in Apple Iphone Os with a CVSS 2.0 base score of 4.3. 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-254.

Key facts

Severity: Medium (CVSS 2.0 base score 4.3)
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-254
Affected product: Apple Iphone Os
Published: 2015-10-23
Last modified: 2026-06-17

Description

The X.509 certificate-trust implementation in Apple iOS before 9.1 does not recognize that the kSecRevocationRequirePositiveResponse flag implies a revocation-checking requirement, which makes it easier for man-in-the-middle attackers to spoof endpoints by leveraging access to a revoked certificate.

Frequently asked questions

What is CVE-2015-6997?: The X.509 certificate-trust implementation in Apple iOS before 9.1 does not recognize that the kSecRevocationRequirePositiveResponse flag implies a revocation-checking requirement, which makes it easier for man-in-the-middle attackers to spoof endpoints by leveraging access to a revoked certificate.
How severe is CVE-2015-6997?: CVE-2015-6997 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2015-6997 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-6997?: CVE-2015-6997 primarily affects Apple Iphone Os. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2015-6997?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-6997 published?: CVE-2015-6997 was published on 2015-10-23 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

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