CVE-2023-36845
CriticalExploitedPublic exploitA PHP External Variable Modification vulnerability in J-Web of Juniper Networks Junos OS on EX Series
Published Aug 18, 2023 · Updated Oct 21, 2025
Key Facts
Patch immediately- CVE-2023-36845 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Junos (Juniper), Junos OS.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Aug 29, 2023. Public exploit code is available.
- EPSS estimates a 95% probability of exploitation in the next 30 days.
- Fixed versions are available, including Junos 20.4, Junos OS 20.4R3-S9, Junos OS 21.1*.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
95%
Higher than 99.8% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2023-36845 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Nov 13, 2023 | Nov 17, 2023 | Not reported |
| Industry KEV feed | Aug 29, 2023 | Nov 17, 2023 | Not reported |
| CIRCL KEV | Oct 22, 2023 | Nov 17, 2023 | Not reported |
| ENISA EUVD | Nov 13, 2023 | n/a | Not reported |
Required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Affected Products
94 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| JunosJuniper | 20.4, 20.4-r1, 20.4-r1-s1, 20.4-r2, 20.4-r2-s1, 20.4-r2-s2, 20.4-r3, 20.4-r3-s1 | 20.4 |
| Junos OS | >= 21.1 | 20.4R3-S9 |
Patched Releases
Junos
20.4
Junos OS
20.4R3-S9, 21.1*, 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
Publicly disclosed
Aug 18, 2023
Added to Industry KEV feed
Aug 29, 2023
Added to CIRCL KEV
Oct 22, 2023
Added to CISA KEV
Nov 13, 2023
Added to ENISA EUVD
Nov 13, 2023
Last updated
Oct 21, 2025
Weakness Type
- CWE-473 PHP External Variable Modification
References
- advisoryhttps://supportportal.juniper.net/JSA72300
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-36844
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-36845
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-36846
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-36847
FAQ
Common Questions.
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.
Affected: Junos (Juniper) versions 20.4, 20.4-r1, 20.4-r1-s1, 20.4-r2, 20.4-r2-s1, 20.4-r2-s2, 20.4-r3, 20.4-r3-s1; Junos OS versions >= 21.1. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Aug 29, 2023.
Yes. It was added on Nov 13, 2023 with a federal remediation due date of Nov 17, 2023.
Public exploit code is available.
Fixed versions are available, including Junos 20.4, Junos OS 20.4R3-S9, Junos OS 21.1*.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Is CVE-2023-36845 Running On Your Attack Surface?
Brandefense maps vulnerabilities like this one to your internet-facing assets and tells you exactly where to patch.
Request A Demo