How severe is CVE-2015-5879?

CVE-2015-5879 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2015-5879 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-5879?

CVE-2015-5879 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-2015-5879?

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

When was CVE-2015-5879 published?

CVE-2015-5879 was published on 2015-09-18 and last updated on 2026-06-17.

CVE-2015-5879

CVE-2015-5879 is a medium-severity vulnerability in Apple Iphone Os with a CVSS 2.0 base score of 5.0. 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-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Apple Iphone Os
Published: 2015-09-18
Last modified: 2026-06-17

Description

XNU in the kernel in Apple iOS before 9 does not properly validate the headers of TCP packets, which allows remote attackers to bypass the sequence-number protection mechanism and cause a denial of service (TCP connection disruption) via a crafted header.

Frequently asked questions

What is CVE-2015-5879?: XNU in the kernel in Apple iOS before 9 does not properly validate the headers of TCP packets, which allows remote attackers to bypass the sequence-number protection mechanism and cause a denial of service (TCP connection disruption) via a crafted header.
How severe is CVE-2015-5879?: CVE-2015-5879 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2015-5879 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-5879?: CVE-2015-5879 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-2015-5879?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-5879 published?: CVE-2015-5879 was published on 2015-09-18 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*

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