How severe is CVE-2015-0639?

CVE-2015-0639 has a CVSS 2.0 base score of 7.8, rated high severity.

Is CVE-2015-0639 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-0639?

CVE-2015-0639 primarily affects Cisco Ios Xe. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2015-0639?

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-2015-0639 published?

CVE-2015-0639 was published on 2015-03-26 and last updated on 2026-06-17.

CVE-2015-0639

CVE-2015-0639 is a high-severity vulnerability in Cisco Ios Xe with a CVSS 2.0 base score of 7.8. 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: High (CVSS 2.0 base score 7.8)
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios Xe
Published: 2015-03-26
Last modified: 2026-06-17

Description

The Common Flow Table (CFT) feature in Cisco IOS XE 3.6 and 3.7 before 3.7.1S, 3.8 before 3.8.0S, 3.9 before 3.9.0S, 3.10 before 3.10.0S, 3.11 before 3.11.0S, 3.12 before 3.12.0S, 3.13 before 3.13.0S, 3.14 before 3.14.0S, and 3.15 before 3.15.0S, when MMON or NBAR is enabled, allows remote attackers to cause a denial of service (device reload) via malformed IPv6 packets with IPv4 UDP encapsulation, aka Bug ID CSCua79665.

Frequently asked questions

What is CVE-2015-0639?: The Common Flow Table (CFT) feature in Cisco IOS XE 3.6 and 3.7 before 3.7.1S, 3.8 before 3.8.0S, 3.9 before 3.9.0S, 3.10 before 3.10.0S, 3.11 before 3.11.0S, 3.12 before 3.12.0S, 3.13 before 3.13.0S, 3.14 before 3.14.0S, and 3.15 before 3.15.0S, when MMON or NBAR is enabled, allows remote attackers to cause a denial of service (device reload) via malformed IPv6 packets with IPv4 UDP encapsulation, aka Bug ID CSCua79665.
How severe is CVE-2015-0639?: CVE-2015-0639 has a CVSS 2.0 base score of 7.8, rated high severity.
Is CVE-2015-0639 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-0639?: CVE-2015-0639 primarily affects Cisco Ios Xe. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2015-0639?: 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-2015-0639 published?: CVE-2015-0639 was published on 2015-03-26 and last updated on 2026-06-17.

References

Affected products (11)

cpe:2.3:o:cisco:ios_xe:3.6s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.6s.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.6s.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.6s.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.7s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.7s.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.7s.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.7s.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.7s.3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.7s.4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.7s.5:*:*:*:*:*:*:*

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