CVE-2021-34798

Name: CVE-2021-34798
Creator: NVD / NIST
Published: 2021-09-16T15:15:07.267+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 64.51%

Last modified Jun 17, 2026

CVE-2021-34798 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Malformed requests may cause the server to dereference a NULL pointer. This issue affects Apache HTTP Server 2.4.48 and earlier.. EPSS estimates a 64.51% chance of exploitation in the next 30 days.

Description

Malformed requests may cause the server to dereference a NULL pointer. This issue affects Apache HTTP Server 2.4.48 and earlier.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

64.51%

99.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Apache	Http Server	<= 2.4.48
Fedoraproject	Fedora	34
Fedoraproject	Fedora	35
Debian	Debian Linux	9.0
Debian	Debian Linux	10.0
Debian	Debian Linux	11.0
Netapp	Cloud Backup	All versions
Netapp	Clustered Data Ontap	All versions
Netapp	Storagegrid	All versions
Tenable	Tenable.Sc	<= 5.19.1
Oracle	Communications Cloud Native Core Network Function Cloud Native Environment	1.10.0
Oracle	Enterprise Manager Base Platform	13.4.0.0
Oracle	Enterprise Manager Base Platform	13.5.0.0
Oracle	Http Server	12.2.1.3.0
Oracle	Http Server	12.2.1.4.0
Oracle	Instantis Enterprisetrack	17.1
Oracle	Instantis Enterprisetrack	17.2
Oracle	Instantis Enterprisetrack	17.3
Oracle	Peoplesoft Enterprise Peopletools	8.58
Oracle	Zfs Storage Appliance Kit	8.8
Broadcom	Brocade Fabric Operating System Firmware	All versions
Siemens	Ruggedcom Nms	All versions
Siemens	Sinec Nms	All versions
Siemens	Sinema Remote Connect Server	< 3.1
Siemens	Sinema Server	14.0

References

http://httpd.apache.org/security/vulnerabilities_24.htmlRelease Notes, Vendor Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-685781.pdfPatch, Third Party Advisory
https://kc.mcafee.com/corporate/index?page=content&id=SB10379Third Party Advisory
https://lists.apache.org/thread.html/r3925e167d5eb1c75def3750c155d753064e1d34a143028bb32910432%40%3Cusers.httpd.apache.org%3E
https://lists.apache.org/thread.html/r61fdbfc26ab170f4e6492ef3bd5197c20b862ce156e9d5a54d4b899c%40%3Cusers.httpd.apache.org%3E
https://lists.apache.org/thread.html/r82838efc5fa6fc4c73986399c9b71573589f78b31846aff5bd9b1697%40%3Cusers.httpd.apache.org%3E
https://lists.apache.org/thread.html/r82c077663f9759c7df5a6656f925b3ee4f55fcd33c889ba7cd687029%40%3Cusers.httpd.apache.org%3E
https://lists.debian.org/debian-lts-announce/2021/10/msg00001.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPBR6WUYBJNACHKE65SPL7TJOHX7RHWD/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNCYSR3BXT36FFF4XTCPL3HDQK4VP45R/
https://security.gentoo.org/glsa/202208-20Third Party Advisory
https://security.netapp.com/advisory/ntap-20211008-0004/Third Party Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-2.4.49-VWL69sWQThird Party Advisory
https://www.debian.org/security/2021/dsa-4982Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory
https://www.tenable.com/security/tns-2021-17Third Party Advisory
http://httpd.apache.org/security/vulnerabilities_24.htmlRelease Notes, Vendor Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-685781.pdfPatch, Third Party Advisory
https://kc.mcafee.com/corporate/index?page=content&id=SB10379Third Party Advisory
https://lists.apache.org/thread.html/r3925e167d5eb1c75def3750c155d753064e1d34a143028bb32910432%40%3Cusers.httpd.apache.org%3E
https://lists.apache.org/thread.html/r61fdbfc26ab170f4e6492ef3bd5197c20b862ce156e9d5a54d4b899c%40%3Cusers.httpd.apache.org%3E
https://lists.apache.org/thread.html/r82838efc5fa6fc4c73986399c9b71573589f78b31846aff5bd9b1697%40%3Cusers.httpd.apache.org%3E
https://lists.apache.org/thread.html/r82c077663f9759c7df5a6656f925b3ee4f55fcd33c889ba7cd687029%40%3Cusers.httpd.apache.org%3E
https://lists.debian.org/debian-lts-announce/2021/10/msg00001.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPBR6WUYBJNACHKE65SPL7TJOHX7RHWD/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNCYSR3BXT36FFF4XTCPL3HDQK4VP45R/
https://security.gentoo.org/glsa/202208-20Third Party Advisory
https://security.netapp.com/advisory/ntap-20211008-0004/Third Party Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-2.4.49-VWL69sWQThird Party Advisory
https://www.debian.org/security/2021/dsa-4982Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory
https://www.tenable.com/security/tns-2021-17Third Party Advisory

Timeline

Published: Sep 16, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-34798?

Malformed requests may cause the server to dereference a NULL pointer. This issue affects Apache HTTP Server 2.4.48 and earlier.

How severe is CVE-2021-34798?

CVE-2021-34798 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 64.51% probability of exploitation in the next 30 days.

How do I fix CVE-2021-34798?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-34798?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST