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CVE-2018-11763· NVD / CVE Program· CNA apache

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

Noroxi assessment

Priority: Monitor (action score 38/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 50.8% (FIRST EPSS); higher than 98.9% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: apache2 (Alpine:v3.10) 2.4.35-r0; apache2 (Debian:12) 2.4.35-1; virtualbox (openSUSE:Leap 15.0) 6.0.10-lp151.2.6.1, 5.2.24-lp150.4.33.1.

Low priority for now. Upgrade to apache2 (Alpine:v3.10) 2.4.35-r0; apache2 (Debian:12) 2.4.35-1; virtualbox (openSUSE:Leap 15.0) 6.0.10-lp151.2.6.1, 5.2.24-lp150.4.33.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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.

MediumCVSS 5.9 · v3.0—No exploit Fix available
Published
Sep 25, 2018
Updated
Jun 16, 2026
EPSS
50.8% · 98th percentile
CWE
—

Report tools

JSON

Action score

38

Monitor

Low priority for now.

CVSS
23 / 40 · 5.9 / 10
CISA KEV
0 / 30 · Not listed
EPSS
15 / 30 · 50.8%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
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  • A fix has been released

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  • when exploit code appears or is weaponized
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  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
apachehttp server
canonicalubuntu linux
redhatenterprise linux
oracleenterprise manager ops center
oraclehospitality guest access
oracleinstantis enterprisetrack
oracleretail xstore point of service
oraclesecure global desktop
netappstorage automation store

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When you'll hear from us

  • when a new CVE affecting this product is published
  • when a record in your stack enters KEV or gets exploit code

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

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Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

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Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • apache http server2.4.17 and later · up to 2.4.34 inclusive

Versions reported by the vendor

Affected version ranges reported by the assigning authority (apache). Independent of NVD's CPE analysis and usually ahead of it.

  • Apache Software Foundation Apache HTTP Server

    • 2.4.17 to 2.4.34affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Alpine:v3.10apache2before 2.4.35-r02.4.35-r0
Debian:12apache2before 2.4.35-12.4.35-1
openSUSE:Leap 15.0virtualboxbefore 6.0.10-lp151.2.6.16.0.10-lp151.2.6.1
openSUSE:Leap 15.0virtualboxbefore 5.2.24-lp150.4.33.15.2.24-lp150.4.33.1
openSUSE:Tumbleweedvirtualboxbefore 6.1.26-3.26.1.26-3.2
Red Hat:jboss_core_services:1::el6jbcs-httpd24before 0:1-6.jbcs.el60:1-6.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apache-commons-daemon-jsvcbefore 1:1.1.0-3.redhat_2.jbcs.el61:1.1.0-3.redhat_2.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apache-commons-daemon-jsvc-debuginfobefore 1:1.1.0-3.redhat_2.jbcs.el61:1.1.0-3.redhat_2.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-aprbefore 0:1.6.3-31.jbcs.el60:1.6.3-31.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-debuginfobefore 0:1.6.3-31.jbcs.el60:1.6.3-31.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-develbefore 0:1.6.3-31.jbcs.el60:1.6.3-31.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-utilbefore 0:1.6.1-24.jbcs.el60:1.6.1-24.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-util-debuginfobefore 0:1.6.1-24.jbcs.el60:1.6.1-24.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-util-develbefore 0:1.6.1-24.jbcs.el60:1.6.1-24.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-util-ldapbefore 0:1.6.1-24.jbcs.el60:1.6.1-24.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-util-mysqlbefore 0:1.6.1-24.jbcs.el60:1.6.1-24.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-util-nssbefore 0:1.6.1-24.jbcs.el60:1.6.1-24.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-util-odbcbefore 0:1.6.1-24.jbcs.el60:1.6.1-24.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-util-opensslbefore 0:1.6.1-24.jbcs.el60:1.6.1-24.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-util-pgsqlbefore 0:1.6.1-24.jbcs.el60:1.6.1-24.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-apr-util-sqlitebefore 0:1.6.1-24.jbcs.el60:1.6.1-24.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-httpdbefore 0:2.4.29-35.jbcs.el60:2.4.29-35.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-httpd-debuginfobefore 0:2.4.29-35.jbcs.el60:2.4.29-35.jbcs.el6
Red Hat:jboss_core_services:1::el6jbcs-httpd24-httpd-develbefore 0:2.4.29-35.jbcs.el60:2.4.29-35.jbcs.el6

+67

Same product

apache: all records

Other highest-scoring records for the same primary product.

  • CVE-2021-42013Path Traversal and Remote Code Execution in Apache HTTP Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773)KEV
    99Now
  • CVE-2021-41773Path traversal and file disclosure vulnerability in Apache HTTP Server 2.4.49KEV
    99Now
  • CVE-2024-38475Apache HTTP Server weakness in mod_rewrite when first segment of substitution matches filesystem path.KEV
    96Now
  • CVE-2019-0211In Apache HTTP Server 2.4 releases 2.4.17 to 2.4.38, with MPM event, worker or prefork, code executing in less-privileged child processes orKEV
    81Now
  • CVE-2021-44790Possible buffer overflow when parsing multipart content in mod_lua of Apache HTTP Server 2.4.51 and earlier
    68This week
  • CVE-2010-0425modules/arch/win32/mod_isapi.c in mod_isapi in the Apache HTTP Server 2.0.37 through 2.0.63, 2.2.0 through 2.2.14, and 2.3.x before 2.3.7, w
    68This week

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
alpine:apache22.4.35-r0 · Alpine:v3.10Package registry (OSV)
debian:apache22.4.35-1 · Debian:12Package registry (OSV)
opensuse:virtualbox5.2.24-lp150.4.33.1 · openSUSE:Leap 15.0Package registry (OSV)
red hat:jbcs-httpd240:1-6.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apache-commons-daemon-jsvc1:1.1.0-3.redhat_2.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apache-commons-daemon-jsvc-debuginfo1:1.1.0-3.redhat_2.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apr0:1.6.3-31.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apr-debuginfo0:1.6.3-31.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apr-devel0:1.6.3-31.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apr-util0:1.6.1-24.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apr-util-debuginfo0:1.6.1-24.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apr-util-devel0:1.6.1-24.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apr-util-ldap0:1.6.1-24.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apr-util-mysql0:1.6.1-24.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
red hat:jbcs-httpd24-apr-util-nss0:1.6.1-24.jbcs.el6 · Red Hat:jboss_core_services:1::el6Package registry (OSV)
suse:apache22.4.33-3.6.1 · SUSE:Linux Enterprise Module for Server Applications 15Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

—

CVSS vector

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (19 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records