CVE-2021-41524

mediumpriority · track · 39EPSS 0.252 · 98 %ileDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

25.2% (98th) EPSS

CVSS 5 · medium

Is it mine?

14 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-476USprimaryCWE-476US

affected products (14)

Products and version ranges known to be affected.

Juniper JUNOSall versionscert_bundDEcpe:/o:juniper:junos:-
Apache Software Foundation Apache HTTP Server≤ 2.4.49enisa_euvdEU
Apache Software Foundation HTTP Server≤ 2.4.49fstec_bduRU
АО «ИВК» Альт 8 СПall versionsfstec_bduRU
АО «Концерн ВНИИНС» ОС ОН «Стрелец»≤ 16.01.2023fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.3fstec_bduRU
apache http server= 2.4.49nvdUScpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
fedoraproject fedora= 34nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
fedoraproject fedora= 35nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
netapp cloud backupall versionsnvdUScpe:2.3:a:netapp:cloud_backup:*:*:*:*:*:*:*:*
oracle instantis enterprisetrack= 17.1nvdUScpe:2.3:a:oracle:instantis_enterprisetrack:*:*:*:*:*:*:*:*
oracle instantis enterprisetrack= 17.2nvdUScpe:2.3:a:oracle:instantis_enterprisetrack:*:*:*:*:*:*:*:*
oracle instantis enterprisetrack= 17.3nvdUScpe:2.3:a:oracle:instantis_enterprisetrack:*:*:*:*:*:*:*:*
Bitnami apache2.4.49 → 2.4.50osvUSpkg:bitnami/apache

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2024-1591Juniper JUNOS: Mehrere SchwachstellenDeutsch2024-07-10csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS ausnutzen, um einen Denial of Service zu verursachen, Informationen offenzulegen, Privilegien zu erweitern und Sicherheitsmechanismen inklusive zu umgehen.
BIT-apache-2021-41524null pointer dereference in h2 fuzzing2024-03-06vendor · osvUS
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.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund nvd osv NVD CVE.org MITRE

published 2021-10-05modified 2026-06-17

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references (32)

External citations — patches, advisories, analysis.

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