How severe is CVE-2012-0339?

CVE-2012-0339 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2012-0339 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-0339?

CVE-2012-0339 primarily affects Cisco Ios. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-0339?

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

When was CVE-2012-0339 published?

CVE-2012-0339 was published on 2012-05-02 and last updated on 2026-06-16.

CVE-2012-0339

CVE-2012-0339 is a medium-severity vulnerability in Cisco Ios 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: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios
Published: 2012-05-02
Last modified: 2026-06-16

Description

Cisco IOS 12.2 through 12.4 and 15.0 does not recognize the vrf-also keyword during enforcement of access-class commands, which allows remote attackers to establish TELNET connections from arbitrary source IP addresses via a standard TELNET client, aka Bug ID CSCsi77774.

Frequently asked questions

What is CVE-2012-0339?: Cisco IOS 12.2 through 12.4 and 15.0 does not recognize the vrf-also keyword during enforcement of access-class commands, which allows remote attackers to establish TELNET connections from arbitrary source IP addresses via a standard TELNET client, aka Bug ID CSCsi77774.
How severe is CVE-2012-0339?: CVE-2012-0339 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2012-0339 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-0339?: CVE-2012-0339 primarily affects Cisco Ios. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-0339?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2012-0339 published?: CVE-2012-0339 was published on 2012-05-02 and last updated on 2026-06-16.

References

Affected products (4)

cpe:2.3:o:cisco:ios:12.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.0:*:*:*:*:*:*:*

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