In Apache HTTP Server 2.4.17 to 2.4.34, by sending continuous, large SETTINGS frames a…
Priority MEDIUM 58Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 10 fixed, 1 without a fix
Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat.
Summary
In Apache HTTP Server 2.4.17 to 2.4.34, by sending continuous, large SETTINGS frames a client can occupy a connection, server thread and CPU time without any connection timeout coming to effect. This affects only HTTP/2 connections. A possible mitigation is to not enable the h2 protocol.
Why it matters now
EPSS 0.51002 98th percentileScored 2026-11-07
Fix Partial Red Hat: 3 advisoriesRed Hat: 10 fixed, 1 without a fix
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Apache | Apache HTTP Server | 2.4.17 to 2.4.34 | — | No fix listed | CNA |
- Apache HTTP Server VendorApache Affected 2.4.17 to 2.4.34 Fixed in — No fix listed CNA
CPE configurations NVD · 17
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:* | 2.4.17 – 2.4.34 | Vulnerable | Apache |
| cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* | 18.04 | Vulnerable | Canonical |
| cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:* | 6.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* | 7.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:7.4:*:*:*:*:*:*:* | 7.4 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:7.5:*:*:*:*:*:*:* | 7.5 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:7.6:*:*:*:*:*:*:* | 7.6 | Vulnerable | Red Hat |
| cpe:2.3:a:oracle:enterprise_manager_ops_center:12.3.3:*:*:*:*:*:*:* | 12.3.3 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:hospitality_guest_access:4.2.0:*:*:*:*:*:*:* | 4.2.0 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:hospitality_guest_access:4.2.1:*:*:*:*:*:*:* | 4.2.1 | Vulnerable | Oracle |
- cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:* Versions 2.4.17 – 2.4.34 Vulnerable ·Apache
- cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical
- cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:7.4:*:*:*:*:*:*:* Versions 7.4 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:7.5:*:*:*:*:*:*:* Versions 7.5 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:7.6:*:*:*:*:*:*:* Versions 7.6 Vulnerable ·Red Hat
- cpe:2.3:a:oracle:enterprise_manager_ops_center:12.3.3:*:*:*:*:*:*:* Versions 12.3.3 Vulnerable ·Oracle
- cpe:2.3:a:oracle:hospitality_guest_access:4.2.0:*:*:*:*:*:*:* Versions 4.2.0 Vulnerable ·Oracle
- cpe:2.3:a:oracle:hospitality_guest_access:4.2.1:*:*:*:*:*:*:* Versions 4.2.1 Vulnerable ·Oracle
Show 7 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:oracle:instantis_enterprisetrack:17.1:*:*:*:*:*:*:* | 17.1 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:instantis_enterprisetrack:17.2:*:*:*:*:*:*:* | 17.2 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:instantis_enterprisetrack:17.3:*:*:*:*:*:*:* | 17.3 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:retail_xstore_point_of_service:7.0:*:*:*:*:*:*:* | 7.0 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:retail_xstore_point_of_service:7.1:*:*:*:*:*:*:* | 7.1 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:secure_global_desktop:5.4:*:*:*:*:*:*:* | 5.4 | Vulnerable | Oracle |
| cpe:2.3:a:netapp:storage_automation_store:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
- cpe:2.3:a:oracle:instantis_enterprisetrack:17.1:*:*:*:*:*:*:* Versions 17.1 Vulnerable ·Oracle
- cpe:2.3:a:oracle:instantis_enterprisetrack:17.2:*:*:*:*:*:*:* Versions 17.2 Vulnerable ·Oracle
- cpe:2.3:a:oracle:instantis_enterprisetrack:17.3:*:*:*:*:*:*:* Versions 17.3 Vulnerable ·Oracle
- cpe:2.3:a:oracle:retail_xstore_point_of_service:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Oracle
- cpe:2.3:a:oracle:retail_xstore_point_of_service:7.1:*:*:*:*:*:*:* Versions 7.1 Vulnerable ·Oracle
- cpe:2.3:a:oracle:secure_global_desktop:5.4:*:*:*:*:*:*:* Versions 5.4 Vulnerable ·Oracle
- cpe:2.3:a:netapp:storage_automation_store:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
Remediation
Red Hat 3 advisories
- RHSA-2019:0367 Released 2019-02-18 · Red Hat rating ImportantRed Hat JBoss Core Services Apache HTTP Server 2.4.29 security update
- Red Hat JBoss Core Services on RHEL 6 Server jbcs-httpd24-1-6.jbcs.el6, jbcs-httpd24-apache-commons-daemon-jsvc-1:1.1.0-3.redhat_2.jbcs.el6, jbcs-httpd24-apr-1.6.3-31.jbcs.el6 +31
- Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-1-6.jbcs.el7, jbcs-httpd24-apache-commons-daemon-jsvc-1:1.1.0-3.redhat_2.jbcs.el7, jbcs-httpd24-apr-1.6.3-31.jbcs.el7 +31
- RHSA-2019:0366 Released 2019-02-18 · Red Hat rating ImportantRed Hat JBoss Core Services Apache HTTP Server 2.4.29 SP1 security update
- Red Hat JBoss Core Services
- RHSA-2018:3558 Released 2018-11-13 · Red Hat rating Moderatehttpd24 security, bug fix, and enhancement update
- Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 6) httpd24-curl-7.61.1-1.el6, httpd24-httpd-2.4.34-7.el6, httpd24-httpd-devel-2.4.34-7.el6 +11
- Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) httpd24-curl-7.61.1-1.el7, httpd24-httpd-2.4.34-7.el7, httpd24-httpd-devel-2.4.34-7.el7 +12
- Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.4) httpd24-curl-7.61.1-1.el7, httpd24-httpd-2.4.34-7.el7, httpd24-httpd-devel-2.4.34-7.el7 +12
- Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.5) httpd24-curl-7.61.1-1.el7, httpd24-httpd-2.4.34-7.el7, httpd24-httpd-devel-2.4.34-7.el7 +12
- Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6) httpd24-curl-7.61.1-1.el7, httpd24-httpd-2.4.34-7.el7, httpd24-httpd-devel-2.4.34-7.el7 +12
- Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 6) httpd24-curl-7.61.1-1.el6, httpd24-httpd-2.4.34-7.el6, httpd24-httpd-devel-2.4.34-7.el6 +11
- Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) httpd24-curl-7.61.1-1.el7, httpd24-httpd-2.4.34-7.el7, httpd24-httpd-devel-2.4.34-7.el7 +12
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Mobile Application Platform 4 | Affected | No fix planned: Will not fix |
| Red Hat JBoss Core Services | Fixed | RHSA-2019:0366 |
| Red Hat JBoss Core Services on RHEL 6 Server | Fixed | RHSA-2019:0367 |
| Red Hat JBoss Core Services on RHEL 7 Server | Fixed | RHSA-2019:0367 |
| Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 6) | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.4) | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.5) | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6) | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 6) | Fixed | RHSA-2018:3558 |
| Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) | Fixed | RHSA-2018:3558 |
Not affected: 8 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat JBoss Enterprise Application Platform 5
- Red Hat JBoss Enterprise Application Platform 6
- Red Hat JBoss Enterprise Web Server 2
- Red Hat JBoss Web Server 3
- Red Hat Virtualization 4
Timeline
- 2026-10-02 Threatist record created from CVE-2018-11763
- 2026-10-03 Alias added: GHSA-c8x9-mqh7-g47j
References
Patch 2
Advisory 9
- RHSA-2018:3558
- https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03909en_us
- https://security.netapp.com/advisory/ntap-20190204-0004/
- RHSA-2019:0367
- USN-3783-1
- https://httpd.apache.org/security/vulnerabilities_24.html
- RHSA-2019:0366
- openSUSE-SU-2019:1547
- openSUSE-SU-2019:1814
Other 13
- [httpd-cvs] 20190815 svn commit: r1048743 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html
- [httpd-cvs] 20190815 svn commit: r1048742 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html
- https://www.tenable.com/security/tns-2019-09
- [httpd-cvs] 20200401 svn commit: r1058586 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html
- [httpd-cvs] 20200401 svn commit: r1058587 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html
- [httpd-cvs] 20210330 svn commit: r1073139 [1/13] - in /websites/staging/httpd/trunk/content: ./ security/json/
- [httpd-cvs] 20210330 svn commit: r1073143 [3/3] - in /websites/staging/httpd/trunk/content: ./ security/
- [httpd-cvs] 20210330 svn commit: r1073140 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/cvejsontohtml.py security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html
- [httpd-cvs] 20210330 svn commit: r1073139 [11/13] - in /websites/staging/httpd/trunk/content: ./ security/json/
- [httpd-cvs] 20210330 svn commit: r1888194 [11/13] - /httpd/site/trunk/content/security/json/
- [httpd-cvs] 20210330 svn commit: r1073149 [1/13] - in /websites/staging/httpd/trunk/content: ./ security/ security/json/
- [httpd-cvs] 20210330 svn commit: r1073149 [11/13] - in /websites/staging/httpd/trunk/content: ./ security/ security/json/
- [httpd-cvs] 20210606 svn commit: r1075470 [4/4] - in /websites/staging/httpd/trunk/content: ./ security/json/CVE-2020-13938.json security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.html
More Apache Http Server vulnerabilities
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- TI-2021-18417 Path traversal and file disclosure vulnerability in Apache HTTP Server 2.4.49 KEVCVSS 3.1CRITICAL 9.8
- TI-2024-25716 Apache HTTP Server weakness in mod_rewrite when first segment of substitution matches filesystem path. KEVCVSS 3.1CRITICAL 9.1
- TI-2021-17490 mod_proxy SSRF KEVCVSS 3.1CRITICAL 9.0
- TI-2019-00184 Use after free in Apache HTTP Server KEVCVSS 3.1HIGH 7.8
- TI-2009-03392 The TLS protocol, and the SSL protocol 3.0 and possibly earlier, as used in Microsoft… CVSS 3.1CRITICAL 9.8
Sources
- CVE-2018-11763 · CVE Program
- CVE-2018-11763 · NVD
- FIRST EPSS
- GHSA-c8x9-mqh7-g47j · GitHub Advisory Database · CC BY 4.0
- CVE-2018-11763 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences