CVE-2016-8740

mediumpriority · attend · 68EPSS 0.791 · 100 %ileexploit · PoCDEEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

3 exploits · PoC

Likely / severe?

79.1% (100th) EPSS

CVSS 5 · medium

Is it mine?

10 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-23

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.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Hsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimaryCWE-399USprimary

exploits (3)

Public proof-of-concept and weaponised exploit code.

EDB-40909Apache 2.4.23 mod_http2 - Denial of ServicePoC · exploit_db
jptr218/apachedosAn implementation of CVE-2016-8740PoC · poc_in_github
lcfpadilha/mac0352-ep4Apache HTTP Server 2.4.23 vulnerability study (CVE-2016-8740)PoC · poc_in_github

affected products (10)

Products and version ranges known to be affected.

Apple macOS <10.13all versionscert_bundDE
Apple macOS< 10.13cert_bundDE
Apache Software Foundation Apache HTTP Server≤ 2.4.17 - 2.4.23enisa_euvdEU
apache http server= 2.4.17nvdUScpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
apache http server= 2.4.18nvdUScpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
apache http server= 2.4.19nvdUScpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
apache http server= 2.4.20nvdUScpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
apache http server= 2.4.21nvdUScpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
apache http server= 2.4.22nvdUScpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
apache http server= 2.4.23nvdUScpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2025-0370Apple Mac OS: Mehrere SchwachstellenDeutsch2017-09-25csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstelle in Apple Mac OS ausnutzen, um Code mit Kernel Privilegien auszuführen, Sicherheitsvorkehrungen zu umgehen, einen Denial of Service Angriff durchzuführen oder vertrauliche Daten einzusehen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2016-12-05modified 2026-06-17

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Related entries.

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+28647 more

references (85)

External citations — patches, advisories, analysis.

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