How severe is CVE-2013-5476?

CVE-2013-5476 has a CVSS 2.0 base score of 7.8, rated high severity.

Is CVE-2013-5476 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-5476?

CVE-2013-5476 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-2013-5476?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2013-5476 published?

CVE-2013-5476 was published on 2013-09-27 and last updated on 2026-06-16.

CVE-2013-5476

CVE-2013-5476 is a high-severity vulnerability in Cisco Ios with a CVSS 2.0 base score of 7.8. 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: High (CVSS 2.0 base score 7.8)
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios
Published: 2013-09-27
Last modified: 2026-06-16

Description

The Zone-Based Firewall (ZFW) feature in Cisco IOS 15.1 through 15.2, when content filtering or HTTP ALG inspection is enabled, allows remote attackers to cause a denial of service (device reload or hang) via crafted IPv4 HTTP traffic, aka Bug ID CSCtx56174.

Frequently asked questions

What is CVE-2013-5476?: The Zone-Based Firewall (ZFW) feature in Cisco IOS 15.1 through 15.2, when content filtering or HTTP ALG inspection is enabled, allows remote attackers to cause a denial of service (device reload or hang) via crafted IPv4 HTTP traffic, aka Bug ID CSCtx56174.
How severe is CVE-2013-5476?: CVE-2013-5476 has a CVSS 2.0 base score of 7.8, rated high severity.
Is CVE-2013-5476 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-5476?: CVE-2013-5476 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-2013-5476?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2013-5476 published?: CVE-2013-5476 was published on 2013-09-27 and last updated on 2026-06-16.

References

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130925-cce

Affected products (2)

cpe:2.3:o:cisco:ios:15.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.2:*:*:*:*:*:*:*

More vulnerabilities in Cisco Ios

CVE-2011-3271 — Critical (CVSS 10.0): Unspecified vulnerability in the Smart Install functionality in Cisco IOS 12.2 and 15.1 allows remote attackers to…
CVE-2011-0935 — Critical (CVSS 10.0): The PKI functionality in Cisco IOS 15.0 and 15.1 does not prevent permanent caching of certain public keys, which…
CVE-2010-1574 — Critical (CVSS 10.0): IOS 12.2(52)SE and 12.2(52)SE1 on Cisco Industrial Ethernet (IE) 3000 series switches has (1) a community name of…
CVE-2010-0581 — Critical (CVSS 10.0): Unspecified vulnerability in the SIP implementation in Cisco IOS 12.3 and 12.4 allows remote attackers to execute…
CVE-2010-0580 — Critical (CVSS 10.0): Unspecified vulnerability in the SIP implementation in Cisco IOS 12.3 and 12.4 allows remote attackers to execute…
CVE-2006-4950 — Critical (CVSS 10.0): Cisco IOS 12.2 through 12.4 before 20060920, as used by Cisco IAD2430, IAD2431, and IAD2432 Integrated Access Devices,…

All CVEs affecting Cisco Ios →

Other CWE-20 (Improper Input Validation) vulnerabilities

CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48281 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48277 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48055 — Critical (CVSS 10.0): Streambert is a cross-platform Electron Desktop App to stream and download any video media. In versions 2.4.0 and…
CVE-2026-34910 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS…
CVE-2026-33587 — Critical (CVSS 10.0): Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and…

Browse all CWE-20 (Improper Input Validation) vulnerabilities →