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Fencer Vulns
critical 9.8

CVE-2023-36845 kev in the critical feed json

Junos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to control an important environment variable

published 2023-08-17 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-40765

cvss
9.8
version 3.1, CNA
cisa kev
Exploited
added 2023-11-13
epss
95.1%
EPSS 95.1% chance of exploitation in 30 days, percentile 99.8%
public exploits
1
Metasploit, plus a Nuclei check

Summary

A PHP External Variable Modification vulnerability in J-Web of Juniper Networks Junos OS on EX Series

and SRX Series

allows an unauthenticated, network-based attacker to remotely execute code.

Using a crafted request which sets the variable PHPRC an attacker is able to modify the PHP execution environment allowing the injection und execution of code.

This issue affects Juniper Networks Junos OS on EX Series

and

SRX Series:

* All versions prior to

20.4R3-S9; * 21.1 versions 21.1R1 and later; * 21.2 versions prior to 21.2R3-S7; * 21.3 versions prior to 21.3R3-S5; * 21.4 versions prior to 21.4R3-S5; * 22.1 versions

prior to

22.1R3-S4; * 22.2 versions

prior to

22.2R3-S2; * 22.3 versions

prior to

22.3R2-S2, 22.3R3-S1; * 22.4 versions

prior to

22.4R2-S1, 22.4R3; * 23.2 versions prior to 23.2R1-S1, 23.2R2.

Patch / fix

cisa required action Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

  • Juniper Networks Junos OS 20.4R3-S9, 21.2R3-S7, 21.3R3-S5, 21.4R3-S5, 22.1R3-S4, 22.2R3-S2, 22.3R2-S2, 22.3R3-S1, 22.4R2-S1, 22.4R3, 23.2R1-S1, 23.2R2

Timeline

  1. First public exploit (Metasploit exploit/freebsd/http/junos_phprc_auto_prepend_file)
  2. Published
  3. Added to CISA KEV
  4. CISA SSVC: exploitation active
  5. CISA patch deadline

Known exploited

Added
2 y ago
Patch by
2023-11-17 (2 y ago)
Ransomware
Not known
Required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Vendor, product
Juniper, Junos OS
CISA name
Juniper Junos OS EX Series and SRX Series PHP External Variable Modification Vulnerability

ATT&CK techniques

How it is exploited and what it leads to, in MITRE ATT&CK terms.

  • T1190 Exploit Public-Facing Application exploitation
  • T1059 Command and Scripting Interpreter primary impact

kev release 2025-07-28, att&ck v16.1. KEV to ATT&CK mappings by the MITRE Center for Threat-Informed Defense (Mappings Explorer, Apache-2.0). © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. Terms of use

CISA SSVC

Exploitation
Active, exploited in the wild
Automatable
yes
Technical impact
total
Assessed
2 y ago

Exploit prediction

95.07% chance of exploitation in the next 30 days, higher than 99.8% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

CVSS scores

assigned by version score vector
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Juniper Networks Junos OS

Classification

Weakness
  • CWE-473 PHP External Variable Modification

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.