CVE-2011-2058

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2011-10-22 · updated 2026-06-16
Weakness: CWE-20

Description

The cat6000-dot1x component in Cisco IOS 12.2 before 12.2(33)SXI7 does not properly handle an external loop between a pair of dot1x enabled ports, which allows remote attackers to cause a denial of service (traffic storm) via unspecified vectors that trigger many unicast EAPoL Protocol Data Units (PDUs), aka Bug ID CSCtq36336.

Affected products

Cisco IOS: from 12.2 before 12.2\(33\)sxi7 — fixed in 12.2\(33\)sxi7

How to fix

Upgrade to a fixed version: Cisco IOS 12.2\(33\)sxi7. Check the vendor advisory for mitigations.

References

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

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