How severe is CVE-2013-6979?

CVE-2013-6979 has a CVSS 2.0 base score of 5.4, rated medium severity.

Is CVE-2013-6979 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-6979?

CVE-2013-6979 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2013-6979?

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

When was CVE-2013-6979 published?

CVE-2013-6979 was published on 2013-12-23 and last updated on 2026-06-17.

CVE-2013-6979

CVE-2013-6979 is a medium-severity vulnerability in Cisco Ios Xe with a CVSS 2.0 base score of 5.4. 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-287.

Key facts

Severity: Medium (CVSS 2.0 base score 5.4)
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Cisco Ios Xe
Published: 2013-12-23
Last modified: 2026-06-17

Description

The VTY authentication implementation in Cisco IOS XE 03.02.xxSE and 03.03.xxSE incorrectly relies on the Linux-IOS internal-network configuration, which allows remote attackers to bypass authentication by leveraging access to a 192.168.x.2 source IP address, aka Bug ID CSCuj90227.

Frequently asked questions

What is CVE-2013-6979?: The VTY authentication implementation in Cisco IOS XE 03.02.xxSE and 03.03.xxSE incorrectly relies on the Linux-IOS internal-network configuration, which allows remote attackers to bypass authentication by leveraging access to a 192.168.x.2 source IP address, aka Bug ID CSCuj90227.
How severe is CVE-2013-6979?: CVE-2013-6979 has a CVSS 2.0 base score of 5.4, rated medium severity.
Is CVE-2013-6979 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-6979?: CVE-2013-6979 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2013-6979?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2013-6979 published?: CVE-2013-6979 was published on 2013-12-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:cisco:ios_xe:-:*:*:*:*:*:*:*

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