NULL pointer dereference in httpd core
Priority HIGH 69CWE-476Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 12 fixed, 2 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-476.
Summary
Malformed requests may cause the server to dereference a NULL pointer. This issue affects Apache HTTP Server 2.4.48 and earlier.
Why it matters now
EPSS 0.64509 99th percentileScored 2026-11-07
Fix Partial Red Hat: 5 advisoriesRed Hat: 12 fixed, 2 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 | Apache HTTP Server 2.4 – 2.4.48 | — | No fix listed | CNA |
- Apache HTTP Server VendorApache Affected Apache HTTP Server 2.4 – 2.4.48 Fixed in — No fix listed CNA
CPE configurations NVD · 25
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:* | up to 2.4.48 | Vulnerable | Apache |
| cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* | 34 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:* | 35 | Vulnerable | Fedoraproject |
| cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Debian |
| cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* | 10.0 | Vulnerable | Debian |
| cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* | 11.0 | Vulnerable | Debian |
| cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:a:netapp:clustered_data_ontap:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:a:netapp:storagegrid:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:a:tenable:tenable.sc:*:*:*:*:*:*:*:* | up to 5.19.1 | Vulnerable | Tenable |
- cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:* Versions up to 2.4.48 Vulnerable ·Apache
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:* Versions 35 Vulnerable ·Fedoraproject
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
- cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian
- cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:a:netapp:clustered_data_ontap:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:a:netapp:storagegrid:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:a:tenable:tenable.sc:*:*:*:*:*:*:*:* Versions up to 5.19.1 Vulnerable ·Tenable
Show 15 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:oracle:communications_cloud_native_core_network_function_cloud_native_environment:1.10.0:*:*:*:*:*:*:* | 1.10.0 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:enterprise_manager_base_platform:13.4.0.0:*:*:*:*:*:*:* | 13.4.0.0 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:enterprise_manager_base_platform:13.5.0.0:*:*:*:*:*:*:* | 13.5.0.0 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:http_server:12.2.1.3.0:*:*:*:*:*:*:* | 12.2.1.3.0 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:http_server:12.2.1.4.0:*:*:*:*:*:*:* | 12.2.1.4.0 | Vulnerable | Oracle |
| 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:peoplesoft_enterprise_peopletools:8.58:*:*:*:*:*:*:* | 8.58 | Vulnerable | Oracle |
| cpe:2.3:a:oracle:zfs_storage_appliance_kit:8.8:*:*:*:*:*:*:* | 8.8 | Vulnerable | Oracle |
| cpe:2.3:o:broadcom:brocade_fabric_operating_system_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | Broadcom |
| cpe:2.3:a:siemens:ruggedcom_nms:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:a:siemens:sinec_nms:*:*:*:*:*:*:*:* | all versions | Vulnerable | Siemens |
| cpe:2.3:a:siemens:sinema_remote_connect_server:*:*:*:*:*:*:*:* | before 3.1 | Vulnerable | Siemens |
| cpe:2.3:a:siemens:sinema_server:14.0:-:*:*:*:*:*:* | 14.0 | Vulnerable | Siemens |
- cpe:2.3:a:oracle:communications_cloud_native_core_network_function_cloud_native_environment:1.10.0:*:*:*:*:*:*:* Versions 1.10.0 Vulnerable ·Oracle
- cpe:2.3:a:oracle:enterprise_manager_base_platform:13.4.0.0:*:*:*:*:*:*:* Versions 13.4.0.0 Vulnerable ·Oracle
- cpe:2.3:a:oracle:enterprise_manager_base_platform:13.5.0.0:*:*:*:*:*:*:* Versions 13.5.0.0 Vulnerable ·Oracle
- cpe:2.3:a:oracle:http_server:12.2.1.3.0:*:*:*:*:*:*:* Versions 12.2.1.3.0 Vulnerable ·Oracle
- cpe:2.3:a:oracle:http_server:12.2.1.4.0:*:*:*:*:*:*:* Versions 12.2.1.4.0 Vulnerable ·Oracle
- 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:peoplesoft_enterprise_peopletools:8.58:*:*:*:*:*:*:* Versions 8.58 Vulnerable ·Oracle
- cpe:2.3:a:oracle:zfs_storage_appliance_kit:8.8:*:*:*:*:*:*:* Versions 8.8 Vulnerable ·Oracle
- cpe:2.3:o:broadcom:brocade_fabric_operating_system_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Broadcom
- cpe:2.3:a:siemens:ruggedcom_nms:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:a:siemens:sinec_nms:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
- cpe:2.3:a:siemens:sinema_remote_connect_server:*:*:*:*:*:*:*:* Versions before 3.1 Vulnerable ·Siemens
- cpe:2.3:a:siemens:sinema_server:14.0:-:*:*:*:*:*:* Versions 14.0 Vulnerable ·Siemens
Remediation
Red Hat 5 advisories
- RHSA-2022:6753 Released 2022-09-29 · Red Hat rating Moderatehttpd24-httpd security and bug fix update
- Red Hat Software Collections for RHEL Workstation(v. 7) httpd24-httpd-2.4.34-23.el7.5, httpd24-httpd-devel-2.4.34-23.el7.5, httpd24-httpd-manual-2.4.34-23.el7.5 +5
- Red Hat Software Collections for RHEL(v. 7) httpd24-httpd-2.4.34-23.el7.5, httpd24-httpd-devel-2.4.34-23.el7.5, httpd24-httpd-manual-2.4.34-23.el7.5 +5
- RHSA-2022:0891 Released 2022-03-15 · Red Hat rating Moderatehttpd:2.4 security update
- Red Hat Enterprise Linux AppStream (v. 8) httpd-2.4.37-43.module+el8.5.0+14370+51c6d843.2.aarch64::httpd:2.4, httpd-2.4.37-43.module+el8.5.0+14370+51c6d843.2.ppc64le::httpd:2.4, httpd-2.4.37-43.module+el8.5.0+14370+51c6d843.2.s390x::httpd:2.4 +38
- RHSA-2022:0143 Released 2022-01-17 · Red Hat rating Importanthttpd security update
- Red Hat Enterprise Linux Client Optional (v. 7) httpd-2.4.6-97.el7_9.4, httpd-devel-2.4.6-97.el7_9.4, httpd-manual-2.4.6-97.el7_9.4 +5
- Red Hat Enterprise Linux ComputeNode Optional (v. 7) httpd-2.4.6-97.el7_9.4, httpd-devel-2.4.6-97.el7_9.4, httpd-manual-2.4.6-97.el7_9.4 +5
- Red Hat Enterprise Linux Server (v. 7) httpd-2.4.6-97.el7_9.4, httpd-devel-2.4.6-97.el7_9.4, httpd-manual-2.4.6-97.el7_9.4 +3
- Red Hat Enterprise Linux Server Optional (v. 7) mod_ldap-2.4.6-97.el7_9.4, mod_proxy_html-1:2.4.6-97.el7_9.4
- Red Hat Enterprise Linux Workstation (v. 7) httpd-2.4.6-97.el7_9.4, httpd-devel-2.4.6-97.el7_9.4, httpd-manual-2.4.6-97.el7_9.4 +3
- Red Hat Enterprise Linux Workstation Optional (v. 7) mod_ldap-2.4.6-97.el7_9.4, mod_proxy_html-1:2.4.6-97.el7_9.4
Show 2 more Red Hat advisories
- RHSA-2021:4614 Released 2021-11-10 · Red Hat rating ModerateRed Hat JBoss Core Services Apache HTTP Server 2.4.37 SP10 security update
- Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-apr-1.6.3-107.jbcs.el7, jbcs-httpd24-apr-devel-1.6.3-107.jbcs.el7, jbcs-httpd24-apr-util-1.6.1-84.jbcs.el7 +36
- Red Hat JBoss Core Services on RHEL 8 jbcs-httpd24-apr-1.6.3-107.el8jbcs, jbcs-httpd24-apr-devel-1.6.3-107.el8jbcs, jbcs-httpd24-apr-util-1.6.1-84.el8jbcs +36
- RHSA-2021:4613 Released 2021-11-10 · Red Hat rating ModerateRed Hat JBoss Core Services Apache HTTP Server 2.4.37 SP10 security update
- Red Hat JBoss Core Services
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Advisory ·
Apache HTTP Server — DSA-4982
4 records Highest priority Priority CRITICAL 1 CRITICAL, 3 HIGH
Other records, highest priority first
- TI-2021-17490 mod_proxy SSRFPriority CRITICAL 98
- TI-2021-16656 ap_escape_quotes buffer overflowPriority HIGH 69
- TI-2021-14579 mod_proxy_uwsgi out of bound readPriority HIGH 68
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat JBoss Enterprise Application Platform 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2022:0891 |
| Red Hat Enterprise Linux Client Optional (v. 7) | Fixed | RHSA-2022:0143 |
| Red Hat Enterprise Linux ComputeNode Optional (v. 7) | Fixed | RHSA-2022:0143 |
| Red Hat Enterprise Linux Server (v. 7) | Fixed | RHSA-2022:0143 |
| Red Hat Enterprise Linux Server Optional (v. 7) | Fixed | RHSA-2022:0143 |
| Red Hat Enterprise Linux Workstation (v. 7) | Fixed | RHSA-2022:0143 |
| Red Hat Enterprise Linux Workstation Optional (v. 7) | Fixed | RHSA-2022:0143 |
| Red Hat JBoss Core Services | Fixed | RHSA-2021:4613 |
| Red Hat JBoss Core Services on RHEL 7 Server | Fixed | RHSA-2021:4614 |
| Red Hat JBoss Core Services on RHEL 8 | Fixed | RHSA-2021:4614 |
| Red Hat Software Collections for RHEL Workstation(v. 7) | Fixed | RHSA-2022:6753 |
| Red Hat Software Collections for RHEL(v. 7) | Fixed | RHSA-2022:6753 |
Not affected: 1 product
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2021-34798
- 2026-10-03 Alias added: GHSA-6cg7-x9gh-4wf6
References
Patch 3
Advisory 10
- http://httpd.apache.org/security/vulnerabilities_24.html
- FEDORA-2021-dce7e7738e
- FEDORA-2021-e3f6dd670d
- [debian-lts-announce] 20211002 [SECURITY] [DLA 2776-1] apache2 security update
- DSA-4982
- 20211124 Multiple Vulnerabilities in Apache HTTP Server Affecting Cisco Products: November 2021
- https://www.tenable.com/security/tns-2021-17
- https://security.netapp.com/advisory/ntap-20211008-0004/
- https://kc.mcafee.com/corporate/index?page=content&id=SB10379
- GLSA-202208-20
Other 4
- [httpd-users] 20210923 [users@httpd] 2.4.49 security fixes: more info
- [httpd-users] 20210923 Re: [users@httpd] 2.4.49 security fixes: more info
- [httpd-users] 20210923 [users@httpd] Re: [External] : [users@httpd] 2.4.49 security fixes: more info
- [httpd-users] 20210923 Re: [users@httpd] Re: [External] : [users@httpd] 2.4.49 security fixes: more info
More Apache Http Server vulnerabilities
- TI-2021-18535 Path Traversal and Remote Code Execution in Apache HTTP Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773) KEVCVSS 3.1CRITICAL 9.8
- 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-2021-34798 · CVE Program
- CVE-2021-34798 · NVD
- FIRST EPSS
- GHSA-6cg7-x9gh-4wf6 · GitHub Advisory Database · CC BY 4.0
- CVE-2021-34798 · 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