CVE-2023-36844

Junos OS: EX Series: A PHP vulnerability in J-Web allows an unauthenticated attacker to control important environment variables

MEDIUM

5.3

CVSS Score

Published: August 17, 2023 at 07:17 PM UTC

Updated: June 17, 2026 at 06:07 AM UTC

63 products affected across 2 vendorsJunosEx4600Ex2300

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Severity

MEDIUM5.3

Exploitation

CISA KEV

Exploit prediction

EPSS 90%

SSVC

Active

Actively Exploited

CISA Known Exploited Vulnerabilities (KEV) Catalog

EPSS Score90.0%

EPSS (Exploit Prediction Scoring System) estimates a 90.0% chance this CVE is exploited in the wild within the next 30 days — higher than 100% of all CVEs. It complements CVSS: a high EPSS on a mid-severity CVE can still be urgent.

Juniper Junos OS on EX Series contains a PHP external variable modification vulnerability that allows an unauthenticated, network-based attacker to control certain, important environment variables. Using a crafted request an attacker is able to modify certain PHP environment variables, leading to partial loss of integrity, which may allow chaining to other vulnerabilities.

Required Action

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

Ransomware Use

Unknown

Added to KEV

Nov 13, 2023

Remediation Due

Nov 17, 2023

1076 days overdue

Notes

https://supportportal.juniper.net/s/article/2023-08-Out-of-Cycle-Security-Bulletin-Junos-OS-SRX-Series-and-EX-Series-Multiple-vulnerabilities-in-J-Web-can-be-combined-to-allow-a-preAuth-Remote-Code-Execution?language=en_US

https://nvd.nist.gov/vuln/detail/CVE-2023-36844

Description

A PHP External Variable Modification vulnerability in J-Web of Juniper Networks Junos OS on EX Series allows an unauthenticated, network-based attacker to control certain, important environment variables. Using a crafted request an attacker is able to modify certain PHP environment variables leading to partial loss of integrity, which may allow chaining to other vulnerabilities. This issue affects Juniper Networks Junos OS on EX 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 22.3R3-S1; * 22.4 versions prior to 22.4R2-S2, 22.4R3; * 23.2 versions prior to 23.2R1-S1, 23.2R2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Junos · Juniper Networks

95%

v < 20.4v < 20.4R3-S921.1 ≤ v < 21.1*21.2 ≤ v < 21.2R3-S621.3 ≤ v < 21.3R3-S521.4 ≤ v < 21.4R3-S522.1 ≤ v < 22.1R3-S422.2 ≤ v < 22.2R3-S222.3 ≤ v < 22.3R3-S122.4 ≤ v < 22.4R2-S2, 22.4R323.2 ≤ v < 23.2R1-S1, 23.2R220.4 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 r3-s2 20.4 r3-s3 20.4 r3-s4 20.4 r3-s5 20.4 r3-s6 20.4 r3-s7 20.4 r3-s8 21.1 21.1 r1 21.1 r1-s1 21.1 r2 21.1 r2-s1 21.1 r2-s2 21.1 r3 21.1 r3-s1 21.1 r3-s2 21.1 r3-s3 21.1 r3-s4 21.1 r3-s5 21.2 21.2 r1 21.2 r1-s1 21.2 r1-s2 21.2 r2 21.2 r2-s1 21.2 r2-s2 21.2 r3 21.2 r3-s1 21.2 r3-s2 21.2 r3-s3 21.2 r3-s4 21.2 r3-s5 21.2 r3-s6 21.3 21.3 r1 21.3 r1-s1 21.3 r1-s2 21.3 r2 21.3 r2-s1 21.3 r2-s2 21.3 r3 21.3 r3-s1 21.3 r3-s2 21.3 r3-s3 21.3 r3-s4 21.4 21.4 r1 21.4 r1-s1 21.4 r1-s2 21.4 r2 21.4 r2-s1 21.4 r2-s2 21.4 r3 21.4 r3-s1 21.4 r3-s2 21.4 r3-s3 21.4 r3-s4 22.1 22.1 r1 22.1 r1-s1 22.1 r1-s2 22.1 r2 22.1 r2-s1 22.1 r2-s2 22.1 r3 22.1 r3-s1 22.1 r3-s2 22.1 r3-s3 22.2 22.2 r1 22.2 r1-s1 22.2 r1-s2 22.2 r2 22.2 r2-s1 22.2 r2-s2 22.2 r3 22.2 r3-s1 22.3 22.3 r1 22.3 r1-s1 22.3 r1-s2 22.3 r2 22.3 r2-s1 22.3 r3 22.4 22.4 r1 22.4 r1-s1 22.4 r1-s2 22.4 r2 23.2 23.2 r1

Affected range stops below 20.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.4R3-S9, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.1*, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.2R3-S6, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.3R3-S5, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.4R3-S5, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.1R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.2R3-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.3R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.4R2-S2, 22.4R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 23.2R1-S1, 23.2R2, so it looks safe — our inference, not a vendor statement

juniper-ex2200 (environment) · juniper-ex2200-c (environment) · juniper-ex2200-vc (environment) · juniper-ex2300 (environment) · juniper-ex2300-24mp (environment) · juniper-ex2300-24p (environment) · juniper-ex2300-24t (environment) · juniper-ex2300-48mp (environment) · juniper-ex2300-48p (environment) · juniper-ex2300-48t (environment) · juniper-ex2300-c (environment) · juniper-ex2300m (environment) · juniper-ex3200 (environment) · juniper-ex3300 (environment) · juniper-ex3300-vc (environment) · juniper-ex3400 (environment) · juniper-ex4200 (environment) · juniper-ex4200-vc (environment) · juniper-ex4300 (environment) · juniper-ex4300-24p (environment) · juniper-ex4300-24p-s (environment) · juniper-ex4300-24t (environment) · juniper-ex4300-24t-s (environment) · juniper-ex4300-32f (environment) · juniper-ex4300-32f-dc (environment) · juniper-ex4300-32f-s (environment) · juniper-ex4300-48mp (environment) · juniper-ex4300-48mp-s (environment) · juniper-ex4300-48p (environment) · juniper-ex4300-48p-s (environment) · juniper-ex4300-48t (environment) · juniper-ex4300-48t-afi (environment) · juniper-ex4300-48t-dc (environment) · juniper-ex4300-48t-dc-afi (environment) · juniper-ex4300-48t-s (environment) · juniper-ex4300-48tafi (environment) · juniper-ex4300-48tdc (environment) · juniper-ex4300-48tdc-afi (environment) · juniper-ex4300-mp (environment) · juniper-ex4300-vc (environment) · juniper-ex4300m (environment) · juniper-ex4400 (environment) · juniper-ex4500 (environment) · juniper-ex4500-vc (environment) · juniper-ex4550 (environment) · juniper-ex4550-vc (environment) · juniper-ex4600 (environment) · juniper-ex4600-vc (environment) · juniper-ex4650 (environment) · juniper-ex6200 (environment) · juniper-ex6210 (environment) · juniper-ex8200 (environment) · juniper-ex8200-vc (environment) · juniper-ex8208 (environment) · juniper-ex8216 (environment) · juniper-ex9200 (environment) · juniper-ex9204 (environment) · juniper-ex9208 (environment) · juniper-ex9214 (environment) · juniper-ex9250 (environment) · juniper-ex9251 (environment) · juniper-ex9253 (environment)

Ex2200 · Juniperdevice

80%

All versions

Ex2200-C · Juniperdevice

80%

All versions

Ex2200-Vc · Juniperdevice

80%

All versions

Ex2300 · Juniperdevice

80%

All versions