How severe is CVE-2011-4231?

CVE-2011-4231 has a CVSS 2.0 base score of 6.3, rated medium severity.

Is CVE-2011-4231 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-4231?

CVE-2011-4231 primarily affects Cisco Ios. In total, 25 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-4231?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2011-4231 published?

CVE-2011-4231 was published on 2012-05-03 and last updated on 2026-06-16.

CVE-2011-4231

CVE-2011-4231 is a medium-severity vulnerability in Cisco Ios with a CVSS 2.0 base score of 6.3. 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: Medium (CVSS 2.0 base score 6.3)
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios
Published: 2012-05-03
Last modified: 2026-06-16

Description

Cisco IOS 15.1 and 15.2 and IOS XE 3.x, when configured as an IPsec hub with X.509 certificates in use, allows remote authenticated users to cause a denial of service (segmentation fault and device crash) via unspecified vectors, aka Bug ID CSCtq61128.

Frequently asked questions

What is CVE-2011-4231?: Cisco IOS 15.1 and 15.2 and IOS XE 3.x, when configured as an IPsec hub with X.509 certificates in use, allows remote authenticated users to cause a denial of service (segmentation fault and device crash) via unspecified vectors, aka Bug ID CSCtq61128.
How severe is CVE-2011-4231?: CVE-2011-4231 has a CVSS 2.0 base score of 6.3, rated medium severity.
Is CVE-2011-4231 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-4231?: CVE-2011-4231 primarily affects Cisco Ios. In total, 25 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-4231?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-4231 published?: CVE-2011-4231 was published on 2012-05-03 and last updated on 2026-06-16.

References

Affected products (25)

cpe:2.3:o:cisco:ios:15.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.1.0s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.1.0sg:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.1.1s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.1.1sg:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.1.2s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.1.3s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.1.4s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.2.0s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.2.0sg:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.2.1s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.2.2s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.3.0s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.3.1s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.3.2s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.3.3s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.4.0as:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.4.0s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.4.1s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.4.2s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.4.3s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.5.0s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.5.1s:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:3.5.2s:*:*:*:*:*:*:*

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