Is CVE-2024-21591 being actively exploited?

CVE-2024-21591 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2024-21591?

CVE-2024-21591 has a CVSS 3.1 base score of 9.8 (CRITICAL).

CVE-2024-21591

CRITICAL · CVSS 9.8EPSS 17.7%EU EUVD

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.

Key facts

CVSS score: 9.8 (v3.1)
Severity: CRITICAL
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-787
EPSS score: 17.7% (97th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2024-19239)
Published: January 12, 2024
NVD last modified: June 17, 2026
Status: Analyzed

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2024-19239 in the EU Vulnerability Database. Last updated in EUVD on October 25, 2024.

View on the EU Vulnerability Database

Affected products

juniper / junos
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and 40 more…

Certified products that may be affected

5 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

Junos Space Network Management Platform, with or without Network Director and with or without Security Director in JA2500 - Juniper Networks, Inc. - FIPS 140 3816 - historical
Juniper Networks SRX345/SRX345-DUAL-AC with Junos 15.1X49-D110 - Juniper Networks, Inc. - FIPS 140 3247 - historical
Junos-FIPS 10.4 L2 OS Cryptographic Module - Juniper Networks, Inc. - FIPS 140 1813 - historical
Junos-FIPS 10.4 L1 OS Cryptographic Module - Juniper Networks, Inc. - FIPS 140 1772 - historical
JUNOS-FIPS - Juniper Networks, Inc. - FIPS 140 602 - historical

References

https://curesec.com/blog/article/CVE-2024-21591_Juniper_Remote_Code_Exec.html(Exploit, Third Party Advisory)
https://supportportal.juniper.net/JSA75729(Vendor Advisory)
https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N(Third Party Advisory)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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