How severe is CVE-2017-6666?

CVE-2017-6666 has a CVSS 3.x base score of 6.0, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2017-6666 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-6666?

CVE-2017-6666 primarily affects Cisco Ios Xr. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-6666?

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

When was CVE-2017-6666 published?

CVE-2017-6666 was published on 2017-06-13 and last updated on 2026-06-17.

CVE-2017-6666

CVE-2017-6666 is a medium-severity vulnerability in Cisco Ios Xr with a CVSS 3.x base score of 6.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 6.0)
CVSS v2: 1.9
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Cisco Ios Xr
Published: 2017-06-13
Last modified: 2026-06-17

Description

A vulnerability in the forwarding component of Cisco IOS XR Software for Cisco Network Convergence System (NCS) 5500 Series Routers could allow an authenticated, local attacker to cause the router to stop forwarding data traffic across Traffic Engineering (TE) tunnels, resulting in a denial of service (DoS) condition. More Information: CSCvd16665. Known Affected Releases: 6.2.11.BASE. Known Fixed Releases: 6.1.3 6.1.2 6.3.1.8i.BASE 6.2.11.8i.BASE 6.2.2.9i.BASE 6.1.32.11i.BASE 6.1.31.10i.BASE 6.1.4.3i.BASE.

Frequently asked questions

What is CVE-2017-6666?: A vulnerability in the forwarding component of Cisco IOS XR Software for Cisco Network Convergence System (NCS) 5500 Series Routers could allow an authenticated, local attacker to cause the router to stop forwarding data traffic across Traffic Engineering (TE) tunnels, resulting in a denial of service (DoS) condition. More Information: CSCvd16665. Known Affected Releases: 6.2.11.BASE. Known Fixed Releases: 6.1.3 6.1.2 6.3.1.8i.BASE 6.2.11.8i.BASE 6.2.2.9i.BASE 6.1.32.11i.BASE 6.1.31.10i.BASE 6.1.4.3i.BASE.
How severe is CVE-2017-6666?: CVE-2017-6666 has a CVSS 3.x base score of 6.0, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2017-6666 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-6666?: CVE-2017-6666 primarily affects Cisco Ios Xr. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-6666?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-6666 published?: CVE-2017-6666 was published on 2017-06-13 and last updated on 2026-06-17.

References

Affected products (9)

cpe:2.3:o:cisco:ios_xr:6.0.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.0.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.0_base:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.1.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.1.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.1.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.1.3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.2.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.2.1:*:*:*:*:*:*:*

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