CVE-2021-41524
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.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 25.2%, higher than 98% of all known CVEs. Patch or mitigate before the next change window.
Description
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 25.17% probability · 98th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- apache/http server · fedoraproject/fedora · oracle/instantis enterprisetrack · netapp/cloud backup
- Source
- security@apache.org
EPSS 25.2% since 3 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.openwall.com/lists/oss-security/2021/10/05/1Mailing List, Third Party Advisory
- https://httpd.apache.org/security/vulnerabilities_24.htmlVendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DSM6UWQICBJ2TU727RENU3HBKEAFLT6T/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EUVJVRJRBW5QVX4OY3NOHZDQ3B3YOTSG/
- https://security.gentoo.org/glsa/202208-20Third Party Advisory
- https://security.netapp.com/advisory/ntap-20211029-0009/Third Party Advisory
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZThird Party Advisory
- https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2021/10/05/1Mailing List, Third Party Advisory
- https://httpd.apache.org/security/vulnerabilities_24.htmlVendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DSM6UWQICBJ2TU727RENU3HBKEAFLT6T/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EUVJVRJRBW5QVX4OY3NOHZDQ3B3YOTSG/
- https://security.gentoo.org/glsa/202208-20Third Party Advisory
- https://security.netapp.com/advisory/ntap-20211029-0009/Third Party Advisory
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZThird Party Advisory
- https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.