CVE-1999-1129

Severity: high (CVSS 7.5 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 1999-09-01 · updated 2026-06-16

Description

Cisco Catalyst 2900 Virtual LAN (VLAN) switches allow remote attackers to inject 802.1q frames into another VLAN by forging the VLAN identifier in the trunking tag.

Affected products

Cisco Catalyst 2900 Vlan: all versions
Cisco IOS: 11.2(8)sa5

References

http://www.cisco.com/univercd/cc/td/doc/product/lan/28201900/1928v8x/eescg8x/aleakyv.htm
http://www.securityfocus.com/archive/1/26008
http://www.securityfocus.com/bid/615
https://exchange.xforce.ibmcloud.com/vulnerabilities/3294
http://www.cisco.com/univercd/cc/td/doc/product/lan/28201900/1928v8x/eescg8x/aleakyv.htm
http://www.securityfocus.com/archive/1/26008
http://www.securityfocus.com/bid/615
https://exchange.xforce.ibmcloud.com/vulnerabilities/3294

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