The ipv6 component in Cisco IOS before 15.1(4)M1.3 allows remote attackers to conduct fingerprinting attacks and obtain potentially sensiti…

published 2011-10-22 15 y ago modified 2026-06-16 4 mo ago also EUVD-2011-2053

cvss: 5.0; version 2.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.6%; EPSS 1.6% chance of exploitation in 30 days, percentile 75%
public exploits: 0; none known

The ipv6 component in Cisco IOS before 15.1(4)M1.3 allows remote attackers to conduct fingerprinting attacks and obtain potentially sensitive information about the presence of the IOS operating system via an ICMPv6 Echo Request packet containing a Hop-by-Hop (HBH) extension header (EH) with a 0x0c01050c value in the PadN option data, aka Bug ID CSCtq02219.

Patch / fix

fixed in 1

cisco ios 15.1\(4\)m1.3

Exploit prediction

1.56% chance of exploitation in the next 30 days, higher than 75% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:P/I:N/A:N

Classification

Weakness

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

Technology feeds

Cisco IOS rss critical rss

References

tools.cisco.com /security/center/viewIpsSignature.x?signatureId=36606&signatureSubId=0
vendor-advisory
blogs.cisco.com /security/1999tcp-redux-the-ipv6-flavor
broken-link

Sources

CVE List CVE-2011-2059
NVD CVE-2011-2059

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary