How severe is CVE-2011-3277?

CVE-2011-3277 has a CVSS 2.0 base score of 7.8, rated high severity.

Is CVE-2011-3277 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-3277?

CVE-2011-3277 primarily affects Cisco Ios Xe. In total, 189 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-3277?

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-2011-3277 published?

CVE-2011-3277 was published on 2011-10-03 and last updated on 2026-06-16.

CVE-2011-3277

CVE-2011-3277 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.

Key facts

Severity: High (CVSS 2.0 base score 7.8)
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Cisco Ios Xe
Published: 2011-10-03
Last modified: 2026-06-16

Description

Unspecified vulnerability in the NAT implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1, and IOS XE 3.1.xSG, allows remote attackers to cause a denial of service (device reload) by sending crafted H.323 packets to TCP port 1720, aka Bug ID CSCth11006.

Frequently asked questions

What is CVE-2011-3277?: Unspecified vulnerability in the NAT implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1, and IOS XE 3.1.xSG, allows remote attackers to cause a denial of service (device reload) by sending crafted H.323 packets to TCP port 1720, aka Bug ID CSCth11006.
How severe is CVE-2011-3277?: CVE-2011-3277 has a CVSS 2.0 base score of 7.8, rated high severity.
Is CVE-2011-3277 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-3277?: CVE-2011-3277 primarily affects Cisco Ios Xe. In total, 189 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-3277?: 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-2011-3277 published?: CVE-2011-3277 was published on 2011-10-03 and last updated on 2026-06-16.

References

Affected products (189)

cpe:2.3:o:cisco:ios_xe:3.1.0sg:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.1.1sg:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.1e:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2b:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2bc:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2bx:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2cx:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2cz:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ew:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ewa:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ex:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ey:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ez:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2fx:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2fy:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2fz:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ira:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2irb:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2irc:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ird:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ire:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2irf:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ixa:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ixb:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ixc:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ixd:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ixe:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ixf:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ixg:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ixh:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2mc:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2mra:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2mrb:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2sb:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2sbc:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2sca:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2scb:*:*:*:*:*:*:*

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