ZDF
Sign inSign up

Vulnerabilities

Vulnerability · CVE-2011-3368

The mod_proxy module in the Apache HTTP Server 1.3.x through 1.3.42, 2.0.x through 2.0.64, and 2.2.x through 2.2.21 does not properly interact with use of (1) RewriteR…

Published Oct 5, 2011 · catalog updated Jun 16, 2026 · http server

Last checked Nov 7, 2026. A connected source was read within the last 7 days.

Check this week

CVE-2011-3368 is not in CISA KEV. FIRST estimates a 90.73% chance of exploitation in the next 30 days. Check whether you run http server.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.

Same product and reporting

Severity
Medium5.0
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
90.73%
Remediation
Advisory link
Affected products
cpe apache/http server

The mod_proxy module in the Apache HTTP Server 1.3.x through 1.3.42, 2.0.x through 2.0.64, and 2.2.x through 2.2.21 does not properly interact with use of (1) RewriteRule and (2) ProxyPassMatch pattern matches for configuration of a reverse proxy, which allows remote attackers to send requests to intranet servers via a malformed URI containing an initial @ (at sign) character.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe apache/http server1.3
  • cpe apache/http server1.3.0
  • cpe apache/http server1.3.1
  • cpe apache/http server1.3.1.1
  • cpe apache/http server1.3.2
  • cpe apache/http server1.3.3

How to fix CVE-2011-3368

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

CVE-2011-3368 is not in CISA KEV. FIRST estimates a 90.73% chance of exploitation in the next 30 days. Check whether you run http server.

Which versions are affected?

Compare what you have installed with apache/http server 1.3; apache/http server 1.3.0; apache/http server 1.3.1; apache/http server 1.3.1.1. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-20: Improper Input Validation. EPSS 90.73%. There is no CISA KEV listing. A public exploit reference is linked in Sources. That is not the same as confirmed exploitation. Use the source links for the original advisory.

Technology hubs

Apache HTTP Server security

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 5, 2011 · Monitored products — critical

    Detected

    The mod_proxy module in the Apache HTTP Server 1.3.x through 1.3.42, 2.0.x through 2.0.64, and 2.2.x through 2.2.21 does not properly interact with use of (1) RewriteRule and (2) ProxyPassMatch pattern matches for configuration of a reverse proxy, which allows remote attackers to send requests to intranet servers via a malformed URI containing an initial @ (at sign) character.

  2. Jun 16, 2026 · Monitored products — critical

    Updated

    The mod_proxy module in the Apache HTTP Server 1.3.x through 1.3.42, 2.0.x through 2.0.64, and 2.2.x through 2.2.21 does not properly interact with use of (1) RewriteRule and (2) ProxyPassMatch pattern matches for configuration of a reverse proxy, which allows remote attackers to send requests to intranet servers via a malformed URI containing an initial @ (at sign) character.

Sources

  • CVE.orgVulnerability recordCVE-2011-3368

    Official CVE identifier

    cve.org
  • Monitored products — criticalVendor advisoryCVE-2011-3368

    The mod_proxy module in the Apache HTTP Server 1.3.x through 1.3.42, 2.0.x through 2.0.64, and 2.2.x through 2.2.21 does not properly interact with use of (1) RewriteRule and (2) ProxyPassMatch pattern matches for configuration of a reverse proxy, which allows remote attackers to send requests to intranet servers via a malformed URI containing an initial @ (at sign) character.

    nvd.nist.gov
  • Metasploit ModulesPublic exploit moduleauxiliary_scanner/http/rewrite_proxy_bypass

    Public module reference (normal). Module source is not copied into this catalog.

    rapid7.com

References

Freshness

Last verified in this catalog Nov 7, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

  • Metasploit ModulesNov 7, 2026
  • CVE.orgNov 4, 2026
  • Monitored products — criticalNov 4, 2026