How severe is CVE-2011-2057?

CVE-2011-2057 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2011-2057 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-2057?

CVE-2011-2057 affects Cisco Ios. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2011-2057?

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-2011-2057 published?

CVE-2011-2057 was published on 2011-10-22 and last updated on 2026-06-16.

CVE-2011-2057

CVE-2011-2057 is a high-severity vulnerability in Cisco Ios with a CVSS 3.x base score of 7.5. 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 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios
Published: 2011-10-22
Last modified: 2026-06-16

Description

The cat6000-dot1x component in Cisco IOS 12.2 before 12.2(33)SXI7 does not properly handle (1) a loop between a dot1x enabled port and an open-authentication dot1x enabled port and (2) a loop between a dot1x enabled port and a non-dot1x port, which allows remote attackers to cause a denial of service (traffic storm) via unspecified vectors that trigger many Spanning Tree Protocol (STP) Bridge Protocol Data Unit (BPDU) frames, aka Bug ID CSCtq36327.

Frequently asked questions

What is CVE-2011-2057?: The cat6000-dot1x component in Cisco IOS 12.2 before 12.2(33)SXI7 does not properly handle (1) a loop between a dot1x enabled port and an open-authentication dot1x enabled port and (2) a loop between a dot1x enabled port and a non-dot1x port, which allows remote attackers to cause a denial of service (traffic storm) via unspecified vectors that trigger many Spanning Tree Protocol (STP) Bridge Protocol Data Unit (BPDU) frames, aka Bug ID CSCtq36327.
How severe is CVE-2011-2057?: CVE-2011-2057 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2011-2057 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-2057?: CVE-2011-2057 affects Cisco Ios. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2011-2057?: 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-2011-2057 published?: CVE-2011-2057 was published on 2011-10-22 and last updated on 2026-06-16.

References

http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SX/release/notes/caveats_SXI_rebuilds.html

Affected products (1)

cpe:2.3:o:cisco:ios:*:*:*:*:*:*:*:*

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