cbcvebase.
CVE-2024-21591
published 2024-01-12

CVE-2024-21591: 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…

PriorityP275critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
17.67%
96.8th percentile
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.

Affected

21 ranges
VendorProductVersion rangeFixed in
juniperex_series
juniperj-web
juniperjunos< 20.420.4
juniperjunos
juniperjunos
juniperjunos
juniperjunos
juniperjunos
juniperjunos
juniperjunos
juniperjunos
juniperjunos_os
junipersrx_series
juniper_networksjunos_os< 20.4R3-S920.4R3-S9
juniper_networksjunos_os>= 21.2 < 21.2R3-S721.2R3-S7
juniper_networksjunos_os>= 21.3 < 21.3R3-S521.3R3-S5
juniper_networksjunos_os>= 21.4 < 21.4R3-S521.4R3-S5
juniper_networksjunos_os>= 22.1 < 22.1R3-S422.1R3-S4
juniper_networksjunos_os>= 22.2 < 22.2R3-S322.2R3-S3
juniper_networksjunos_os>= 22.3 < 22.3R3-S222.3R3-S2
juniper_networksjunos_os>= 22.4 < 22.4R2-S2, 22.4R322.4R2-S2, 22.4R3

Detection & IOCsextracted from sources · hover to see the quote

  • The attack surface is the J-Web interface exposed on Juniper SRX Series firewalls and EX Series switches; disabling or restricting J-Web access removes the attack vector for unauthenticated exploitation.
  • Over 8,200 Juniper devices have J-Web interfaces exposed online (Shadowserver data); over 9,000 tracked by Shodan — prioritize detection/blocking of internet-facing J-Web endpoints.
  • The vulnerability is an out-of-bounds write caused by use of an insecure function allowing arbitrary memory overwrite, exploitable by unauthenticated network-based attackers for RCE with root privileges or DoS on J-Web.
  • Restrict J-Web access to only trusted network hosts as a temporary mitigation until patches are deployed to reduce exposure.
  • ·No active in-the-wild exploitation was observed at time of disclosure; however, past Juniper J-Web vulnerabilities (CVE-2023-36844/36845/36846/36847) were exploited within one week of patch release and PoC publication, suggesting rapid weaponization is likely.
  • ·Affected platforms are Junos OS SRX Series and EX Series only; patched versions are 20.4R3-S9, 21.2R3-S7, 21.3R3-S5, 21.4R3-S5, 22.1R3-S4, 22.2R3-S3, 22.3R3-S2, 22.4R2-S2, 22.4R3, 23.2R1-S1, 23.2R2, 23.4R1, and all subsequent releases.
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