Skip to content

Technology

Apache HTTP Server vulnerabilities

The Apache httpd web server. 553 published CVES affecting Apache HTTP Server, from public sources (CVE.org, NVD, CISA KEV, FIRST EPSS, OSV).

Total
553
Critical
46
High
179
Medium
242
Low
28
Unscored
58
CISA KEV
11
Atom feed of Apache HTTP Server alerts

Latest Apache HTTP Server CVEs

Newest publication first · page 10 of 23

  1. CriticalCVSS 9.1 EPSS 56.8%

    In Apache httpd before 2.2.34 and 2.4.x before 2.4.27, the value placeholder in [Proxy-]Authorization headers of type 'Digest' was not initialized or reset before or between successive key=value assignments by mod_auth_digest. Providing an initial key with no '=' assignment could...

  2. HighCVSS 7.5 EPSS 57.5%

    The HTTP strict parsing changes added in Apache httpd 2.2.32 and 2.4.24 introduced a bug in token list parsing, which allows ap_find_token() to search past the end of its input string. By maliciously crafting a sequence of request headers, an attacker may be able to cause a segme...

  3. HighCVSS 7.5 EPSS 2.9%

    An issue was discovered in PHP 5.x and 7.x, when the configuration uses apache2handler/mod_php or php-fpm with OpCache enabled. With 5.x after 5.6.28 or 7.x after 7.0.13, the issue is resolved in a non-default configuration with the opcache.validate_permission=1 setting. The vuln...

  4. HighCVSS 8.6 EPSS 4.3%

    The "OpenID Connect Relying Party and OAuth 2.0 Resource Server" (aka mod_auth_openidc) module before 2.1.6 for the Apache HTTP Server does not skip OIDC_CLAIM_ and OIDCAuthNHeader headers in an "AuthType oauth20" configuration, which allows remote attackers to bypass authenticat...

  5. HighCVSS 8.6 EPSS 3.6%

    The "OpenID Connect Relying Party and OAuth 2.0 Resource Server" (aka mod_auth_openidc) module before 2.1.5 for the Apache HTTP Server does not skip OIDC_CLAIM_ and OIDCAuthNHeader headers in an "OIDCUnAuthAction pass" configuration, which allows remote attackers to bypass authen...

  6. HighCVSS 7.5 EPSS 6.6%

    Information disclosure and authentication bypass vulnerability exists in the Apache HTTP Server configuration bundled with ZoneMinder v1.30 and v1.29, which allows a remote unauthenticated attacker to browse all directories in the web root, e.g., a remote unauthenticated attacker...

  7. HighCVSS 7.5 EPSS 79.1%

    The mod_http2 module in the Apache HTTP Server 2.4.17 through 2.4.23, when the Protocols configuration includes h2 or h2c, does not restrict request-header length, which allows remote attackers to cause a denial of service (memory consumption) via crafted CONTINUATION frames in a...

  8. HighCVSS 7.5 EPSS 3.6%

    mod_cluster, as used in Red Hat JBoss Web Server 2.1, allows remote attackers to cause a denial of service (Apache http server crash) via an MCMP message containing a series of = (equals) characters after a legitimate element.

  9. CriticalCVSS 9.1 EPSS 1.3%

    The Apache HTTP Server in Apple OS X before 10.12 and OS X Server before 5.2 follows RFC 3875 section 4.1.18 and therefore does not protect applications from the presence of untrusted CGI client data in the HTTP_PROXY environment variable, which might allow remote attackers to re...

  10. HighCVSS 8.1 EPSS 55.7%

    The Apache HTTP Server through 2.4.23 follows RFC 3875 section 4.1.18 and therefore does not protect applications from the presence of untrusted client data in the HTTP_PROXY environment variable, which might allow remote attackers to redirect an application's outbound HTTP traff...

  11. HighCVSS 7.5 EPSS 18.8%

    The Apache HTTP Server 2.4.18 through 2.4.20, when mod_http2 and mod_ssl are enabled, does not properly recognize the "SSLVerifyClient require" directive for HTTP/2 request authorization, which allows remote attackers to bypass intended access restrictions by leveraging the abili...

  12. MediumCVSS 5.9 EPSS 15.9%

    The Apache HTTP Server 2.4.17 and 2.4.18, when mod_http2 is enabled, does not limit the number of simultaneous stream workers for a single HTTP/2 connection, which allows remote attackers to cause a denial of service (stream-processing outage) via modified flow-control windows.

Sources: CVE.org, NVD, CISA KEV, FIRST EPSS, OSV and public exploit-reference metadata. Product matching comes from the published CVE records. A proof-of-concept means public code exists; it is not evidence of exploitation.