// For flags

CVE-2016-8740

Apache 2.4.23 mod_http2 - Denial of Service

Severity Score

7.5
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

2
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

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 an HTTP/2 request.

El módulo mod_http2 en el Apache HTTP Server 2.4.17 hasta la versión 2.4.23, cuando la configuración Protocols incluye h2 o h2c, no restringe la longitud de la cabecera de petición, lo que permite a atacantes remotos provocar una denegación de servicio (corrupción de memoria) a través de marcos CONTINUATION manipulados en una petición HTTP/2.

A vulnerability was found in httpd's handling of the LimitRequestFields directive in mod_http2, affecting servers with HTTP/2 enabled. An attacker could send crafted requests with headers larger than the server's available memory, causing httpd to crash.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
Attack Vector
Network
Attack Complexity
Medium
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2016-10-18 CVE Reserved
  • 2016-12-05 CVE Published
  • 2024-08-06 CVE Updated
  • 2024-08-06 First Exploit
  • 2024-09-27 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-20: Improper Input Validation
  • CWE-399: Resource Management Errors
  • CWE-770: Allocation of Resources Without Limits or Throttling
CAPEC
References (30)
URL Tag Source
http://www.securityfocus.com/bid/94650 Third Party Advisory
http://www.securitytracker.com/id/1037388 Third Party Advisory
https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03725en_us X_refsource_confirm
https://lists.apache.org/thread.html/56c2e7cc9deb1c12a843d0dc251ea7fd3e7e80293cde02fcd65286ba%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/84a3714f0878781f6ed84473d1a503d2cc382277e100450209231830%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/r04e89e873d54116a0635ef2f7061c15acc5ed27ef7500997beb65d6f%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/r476d175be0aaf4a17680ef98c5153b4d336eaef76fb2224cc94c463a%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/r76142b8c5119df2178be7c2dba88fde552eedeec37ea993dfce68d1d%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/r9f93cf6dde308d42a9c807784e8102600d0397f5f834890708bf6920%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/rb14daf9cc4e28d18cdc15d6a6ca74e565672fabf7ad89541071d008b%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/rc998b18880df98bafaade071346690c2bc1444adaa1a1ea464b93f0a%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/rcc44594d4d6579b90deccd4536b5d31f099ef563df39b094be286b9e%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/rd18c3c43602e66f9cdcf09f1de233804975b9572b0456cc582390b6f%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/rd336919f655b7ff309385e34a143e41c503e133da80414485b3abcc9%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/re1e3a24664d35bcd0a0e793e0b5fc6ca6c107f99a1b2c545c5d4b467%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/re3d27b6250aa8548b8845d314bb8a350b3df326cacbbfdfe4d455234%40%3Ccvs.httpd.apache.org%3E Mailing List
https://lists.apache.org/thread.html/rf6449464fd8b7437704c55f88361b66f12d5b5f90bcce66af4be4ba9%40%3Ccvs.httpd.apache.org%3E Mailing List
https://security.netapp.com/advisory/ntap-20180423-0001 X_refsource_confirm
https://support.apple.com/HT208221 X_refsource_confirm
https://www.tenable.com/security/tns-2017-04 X_refsource_confirm
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Apache
Search vendor "Apache"
Http Server
Search vendor "Apache" for product "Http Server"
2.4.17
Search vendor "Apache" for product "Http Server" and version "2.4.17"
-
Affected
Apache
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Http Server
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2.4.18
Search vendor "Apache" for product "Http Server" and version "2.4.18"
-
Affected
Apache
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Http Server
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2.4.19
Search vendor "Apache" for product "Http Server" and version "2.4.19"
-
Affected
Apache
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Http Server
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2.4.20
Search vendor "Apache" for product "Http Server" and version "2.4.20"
-
Affected
Apache
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Http Server
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2.4.21
Search vendor "Apache" for product "Http Server" and version "2.4.21"
-
Affected
Apache
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Http Server
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2.4.22
Search vendor "Apache" for product "Http Server" and version "2.4.22"
-
Affected
Apache
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Http Server
Search vendor "Apache" for product "Http Server"
2.4.23
Search vendor "Apache" for product "Http Server" and version "2.4.23"
-
Affected