How severe is CVE-2007-6203?

CVE-2007-6203 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2007-6203 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 81% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2007-6203?

CVE-2007-6203 primarily affects Apache Http Server. In total, 25 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2007-6203?

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

When was CVE-2007-6203 published?

CVE-2007-6203 was published on 2007-12-03 and last updated on 2026-06-16.

CVE-2007-6203

CVE-2007-6203 is a medium-severity vulnerability in Apache Http Server with a CVSS 2.0 base score of 4.3. Its EPSS exploit-prediction score of 81% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 2.0 base score 4.3)
EPSS exploit prediction: 81% (100th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Apache Http Server
Published: 2007-12-03
Last modified: 2026-06-16

Description

Apache HTTP Server 2.0.x and 2.2.x does not sanitize the HTTP Method specifier header from an HTTP request when it is reflected back in a "413 Request Entity Too Large" error message, which might allow cross-site scripting (XSS) style attacks using web client components that can send arbitrary headers in requests, as demonstrated via an HTTP request containing an invalid Content-length value, a similar issue to CVE-2006-3918.

Frequently asked questions

What is CVE-2007-6203?: Apache HTTP Server 2.0.x and 2.2.x does not sanitize the HTTP Method specifier header from an HTTP request when it is reflected back in a "413 Request Entity Too Large" error message, which might allow cross-site scripting (XSS) style attacks using web client components that can send arbitrary headers in requests, as demonstrated via an HTTP request containing an invalid Content-length value, a similar issue to CVE-2006-3918.
How severe is CVE-2007-6203?: CVE-2007-6203 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2007-6203 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 81% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2007-6203?: CVE-2007-6203 primarily affects Apache Http Server. In total, 25 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2007-6203?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2007-6203 published?: CVE-2007-6203 was published on 2007-12-03 and last updated on 2026-06-16.

References

Affected products (25)

cpe:2.3:a:apache:http_server:2.0.46:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.47:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.48:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.49:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.50:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.51:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.52:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.53:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.54:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.55:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.57:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.58:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.0.59:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.1.1:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.1.2:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.1.3:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.1.4:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.1.5:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.1.6:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.1.7:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.1.8:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.2.0:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.2.2:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.2.3:*:*:*:*:*:*:*
cpe:2.3:a:apache:http_server:2.2.4:*:*:*:*:*:*:*

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Other CWE-79 (Cross-site Scripting (XSS)) vulnerabilities

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CVE-2024-47875 — Critical (CVSS 10.0): DOMPurify is a DOM-only, super-fast, uber-tolerant XSS sanitizer for HTML, MathML and SVG. DOMpurify was vulnerable to…
CVE-2024-6886 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Gitea…
CVE-2023-45144 — Critical (CVSS 10.0): com.xwiki.identity-oauth:identity-oauth-ui is a package to aid in building identity and service providers based on…
CVE-2023-45138 — Critical (CVSS 10.0): Change Request is an pplication allowing users to request changes on a wiki without publishing the changes directly.…
CVE-2022-4361 — Critical (CVSS 10.0): Keycloak, an open-source identity and access management solution, has a cross-site scripting (XSS) vulnerability in the…

Browse all CWE-79 (Cross-site Scripting (XSS)) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

222.99.52.202 (ipv4-addr)
218.4.156.254 (ipv4-addr)
41.224.62.206 (ipv4-addr)
171.100.156.38 (ipv4-addr)