CubePath
Sign Up

CVE-2023-36844

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

CVSS 3.1 Medium 5.3Known exploited (CISA KEV)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

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.

Official description from the CVE record, published by juniper. Copyright © 1999-2026 The MITRE Corporation. See /security/cve/legal for the CVE license. View the record on cve.org

Key data

CVSS 3.1 Medium 5.3

Score published by juniper in the CVE record.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

  • Attack vector: Network

    The vulnerable component can be reached over a network, possibly from the Internet.

  • Attack complexity: Low

    No special conditions are needed. The attack can be repeated at will.

  • Privileges required: None

    No account or privileges are needed.

  • User interaction: None

    No action from any user is needed.

  • Scope: Unchanged

    The impact stays within the vulnerable component.

  • Confidentiality impact: None

    No effect on the secrecy of data.

  • Integrity impact: Low

    Limited effect on the trustworthiness of data.

  • Availability impact: None

    No effect on availability.

CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at first.org/cvss.

EPSS

Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days.
Score
0.89958 (90.0% probability)
Percentile
99.8%
Scores of
Nov 10, 2026
Model
v2026.06.15

CISA Known Exploited Vulnerabilities

This CVE is listed in the CISA KEV catalog.
Name in the catalog
Juniper Junos OS EX Series PHP External Variable Modification Vulnerability
Added to the catalog
Nov 13, 2023
Federal due date
Nov 17, 2023

CISA assessment as of Nov 15, 2023

Stakeholder-Specific Vulnerability Categorization (SSVC) decision points added by CISA.
Exploitation
Recorded by CISA as active
Automatable
yes
Technical impact
total

Weakness (CWE)

CWE catalog version 5.0.
CWE names: Copyright © 2006-2026, The MITRE Corporation. See /security/cve/legal for the CWE license.
  • CWE-473PHP External Variable Modification

Affected products

Products listed in the CVE record, as the CNA published them.

  • Juniper Networks Junos OS

    • affected: before 20.4R3-S9
    • affected: 21.1 up to before 21.1*
    • affected: 21.2 up to before 21.2R3-S6
    • affected: 21.3 up to before 21.3R3-S5
    • affected: 21.4 up to before 21.4R3-S5
    • affected: 22.1 up to before 22.1R3-S4
    • affected: 22.2 up to before 22.2R3-S2
    • affected: 22.3 up to before 22.3R3-S1
    • affected: 22.4 up to before 22.4R2-S2, 22.4R3
    • affected: 23.2 up to before 23.2R1-S1, 23.2R2

References

Links listed in the CVE record. They lead to other sites, which CubePath does not control.

Timeline

  1. ID reserved
  2. Record published
  3. Added to CISA KEV
  4. Record last updated

Look up another CVE

About CubePath

CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection.
Cloud VPSDDoS protection

Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:24 UTC. Sources and licenses