CVE-2024-21591

criticalpriority · attend · 45EPSS 0.177 · 97 %ileDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

17.7% (97th) EPSS

CVSS 9.8 · critical

Is it mine?

42 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-26

An Out-of-bounds Write vulnerability in J-Web of Juniper Networks Junos OS on SRX Series and EX Series allows an unauthenticated, network-based attacker to cause a Denial of Service (DoS), or Remote Code Execution (RCE) and obtain root privileges on the device. This issue is caused by use of an insecure function allowing an attacker to overwrite arbitrary memory. This issue affects Juniper Networks Junos OS SRX Series and EX Series: * Junos OS versions earlier than 20.4R3-S9; * Junos OS 21.2 versions earlier than 21.2R3-S7; * Junos OS 21.3 versions earlier than 21.3R3-S5; * Junos OS 21.4 versions earlier than 21.4R3-S5; * Junos OS 22.1 versions earlier than 22.1R3-S4; * Junos OS 22.2 versions earlier than 22.2R3-S3; * Junos OS 22.3 versions earlier than 22.3R3-S2; * Junos OS 22.4 versions earlier than 22.4R2-S2, 22.4R3.

cvss

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

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · sirt@juniper.net USexploitability 3.9 · impact 5.9

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-787USprimaryCWE-787US

affected products (42)

Products and version ranges known to be affected.

Juniper EX Seriesall versionscert_bundDEcpe:/h:juniper:ex:-
Juniper EX Series 4100all versionscert_bundDEcpe:/h:juniper:ex:4100
Juniper EX Series 4400all versionscert_bundDEcpe:/h:juniper:ex:4400
Juniper EX Series 4600all versionscert_bundDEcpe:/h:juniper:ex:ex4600
Juniper EX Series EX9200all versionscert_bundDEcpe:/h:juniper:ex:ex9200
Juniper JUNOSall versionscert_bundDEcpe:/o:juniper:junos:-
Juniper JUNOS ACX7024all versionscert_bundDEcpe:/o:juniper:junos:acx7024
Juniper JUNOS ACX7100-32Call versionscert_bundDEcpe:/o:juniper:junos:acx7100-32c
Juniper JUNOS ACX7100-48Lall versionscert_bundDEcpe:/o:juniper:junos:acx7100-48l
Juniper JUNOS Evolvedall versionscert_bundDEcpe:/o:juniper:junos:evolved
Juniper JUNOS PTX Seriesall versionscert_bundDEcpe:/o:juniper:junos:ptx_series
Juniper Junos Space <24.1R2all versionscert_bundDE
Juniper MX Seriesall versionscert_bundDEcpe:/h:juniper:mx:-
Juniper QFX Series 5000all versionscert_bundDEcpe:/h:juniper:qfx:qfx5000
Juniper SRX Seriesall versionscert_bundDEcpe:/h:juniper:srx_service_gateways:-
Juniper Junos Space< 24.1R2cert_bundDE
Juniper Networks Junos OSall versionsenisa_euvdEU
Juniper Networks Junos OS0 → 20.4R3-S9enisa_euvdEU
Juniper Networks Junos OS21.2 → 21.2R3-S7enisa_euvdEU
Juniper Networks Junos OS21.3 → 21.3R3-S5enisa_euvdEU

showing 20 of 42

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2024-0064Juniper Produkte: Mehrere SchwachstellenDeutsch2024-01-10csaf · cert_bundDE
Ein Angreifer aus dem angrenzenden Netzwerk oder ein entfernter, anonymer, authentisierter, lokaler oder physischer Angreifer kann mehrere Schwachstellen in Juniper JUNOS, Juniper JUNOS Evolved, Juniper SRX Series, Juniper EX Series, Juniper QFX Series, Juniper ACX Series, Juniper PTX Series und Juniper MX Series ausnutzen, um beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand herbeizuführen und seine Berechtigungen zu erweitern.

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 CVE.org MITRE

published 2024-01-12modified 2026-06-17

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+16091 more

references (11)

External citations — patches, advisories, analysis.

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