How severe is CVE-2015-4203?

CVE-2015-4203 has a CVSS 2.0 base score of 5.4, rated medium severity.

Is CVE-2015-4203 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-4203?

CVE-2015-4203 primarily affects Cisco Ios. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2015-4203?

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

When was CVE-2015-4203 published?

CVE-2015-4203 was published on 2015-06-23 and last updated on 2026-06-17.

CVE-2015-4203

CVE-2015-4203 is a medium-severity vulnerability in Cisco Ios with a CVSS 2.0 base score of 5.4. 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-362.

Key facts

Severity: Medium (CVSS 2.0 base score 5.4)
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-362
Affected product: Cisco Ios
Published: 2015-06-23
Last modified: 2026-06-17

Description

Race condition in Cisco IOS 12.2SCH in the Performance Routing Engine (PRE) module on uBR10000 devices, when NetFlow and an MPLS IPv6 VPN are configured, allows remote attackers to cause a denial of service (PXF process crash) by sending malformed MPLS 6VPE packets quickly, aka Bug ID CSCud83396.

Frequently asked questions

What is CVE-2015-4203?: Race condition in Cisco IOS 12.2SCH in the Performance Routing Engine (PRE) module on uBR10000 devices, when NetFlow and an MPLS IPv6 VPN are configured, allows remote attackers to cause a denial of service (PXF process crash) by sending malformed MPLS 6VPE packets quickly, aka Bug ID CSCud83396.
How severe is CVE-2015-4203?: CVE-2015-4203 has a CVSS 2.0 base score of 5.4, rated medium severity.
Is CVE-2015-4203 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-4203?: CVE-2015-4203 primarily affects Cisco Ios. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2015-4203?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-4203 published?: CVE-2015-4203 was published on 2015-06-23 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:cisco:ios:12.2\(33\)sch:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2sch:*:*:*:*:*:*:*

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