null pointer dereference in h2 fuzzing
Priority MEDIUM 54CWE-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: 2 fixed, 1 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-476.
Summary
While fuzzing the 2.4.49 httpd, a new null pointer dereference was detected during HTTP/2 request processing, allowing an external source to DoS the server. This requires a specially crafted request. The vulnerability was recently introduced in version 2.4.49. No exploit is known to the project.
Why it matters now
EPSS 0.25804 97th percentileScored 2026-11-07
Fix Partial Red Hat: 2 advisoriesRed Hat: 2 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 | 2.4.49 | — | No fix listed | CNA |
- Apache HTTP Server VendorApache Affected 2.4.49 Fixed in — No fix listed CNA
CPE configurations NVD · 7
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:apache:http_server:2.4.49:*:*:*:*:*:*:* | 2.4.49 | 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: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:netapp:cloud_backup:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
- cpe:2.3:a:apache:http_server:2.4.49:*:*:*:*:*:*:* Versions 2.4.49 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: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:netapp:cloud_backup:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
Remediation
Red Hat 2 advisories
- RHSA-2022:7143 Released 2022-10-26 · Red Hat rating ModerateRed Hat JBoss Core Services Apache HTTP Server 2.4.51 security update
- Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-httpd-2.4.51-28.el7jbcs, jbcs-httpd24-httpd-devel-2.4.51-28.el7jbcs, jbcs-httpd24-httpd-manual-2.4.51-28.el7jbcs +6
- Red Hat JBoss Core Services on RHEL 8 jbcs-httpd24-httpd-2.4.51-28.el8jbcs, jbcs-httpd24-httpd-devel-2.4.51-28.el8jbcs, jbcs-httpd24-httpd-manual-2.4.51-28.el8jbcs +6
- RHSA-2022:7144 Released 2022-10-26 · Red Hat rating ImportantRed Hat JBoss Core Services Apache HTTP Server 2.4.51 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 — 20211007 Apache HTTP Server Vulnerabilties: October 2021
3 records Highest priority Priority CRITICAL 2 CRITICAL, 1 MEDIUM
Other records, highest priority first
- 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)Priority CRITICAL 100
- TI-2021-18417 Path traversal and file disclosure vulnerability in Apache HTTP Server 2.4.49Priority CRITICAL 100
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat JBoss Enterprise Application Platform 6 | Affected | No fix planned: Out of support scope |
| Red Hat JBoss Core Services on RHEL 7 Server | Fixed | RHSA-2022:7143 |
| Red Hat JBoss Core Services on RHEL 8 | Fixed | RHSA-2022:7143 |
Not affected: 7 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat JBoss Core Services on RHEL 7 Server
- Red Hat JBoss Core Services on RHEL 8
- Red Hat Software Collections
Timeline
- 2026-10-02 Threatist record created from CVE-2021-41524
- 2026-10-03 Alias added: GHSA-f29c-hjcq-ww2f
- 2026-10-09 Fix available: RHSA-2022:7144 · Red Hat
References
Advisory 7
- https://httpd.apache.org/security/vulnerabilities_24.html
- [oss-security] 20211005 CVE-2021-41524: Apache HTTP Server: null pointer dereference in h2 fuzzing
- FEDORA-2021-5d2d4b6ac5
- 20211007 Apache HTTP Server Vulnerabilties: October 2021
- FEDORA-2021-f94985afca
- https://security.netapp.com/advisory/ntap-20211029-0009/
- GLSA-202208-20
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-2021-41524 · CVE Program
- CVE-2021-41524 · NVD
- FIRST EPSS
- GHSA-f29c-hjcq-ww2f · GitHub Advisory Database · CC BY 4.0
- CVE-2021-41524 · 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