Juniper Networks Remote Code Execution Exploit Detection
Description
The following analytic detects the exploitation of a remote code execution vulnerability in Juniper Networks devices. The vulnerability involves multiple steps, including uploading a malicious PHP file and an INI file to the target server, and then executing the PHP code by manipulating the PHP configuration via the uploaded INI file. The analytic specifically looks for requests to /webauth_operation.php?PHPRC=*, which are used to upload the files and execute the code, respectively. This behavior is worth identifying for a SOC because it indicates that an attacker is attempting to exploit the vulnerability to gain unauthorized access to the device and execute arbitrary code. If a true positive is found, it suggests that an attacker has successfully exploited the vulnerability and may have gained control over the device, leading to data theft, network compromise, or other damaging outcomes. Upon triage, review the request parameters and the response to determine if the exploitation was successful. Capture and inspect any relevant network traffic and server logs to identify the attack source. This approach helps analysts detect potential threats earlier and mitigate the risks.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Web
- Last Updated: 2023-08-29
- Author: Michael Haag, Splunk
- ID: 6cc4cc3d-b10a-4fac-be1e-55d384fc690e
Annotations
ATT&CK
Kill Chain Phase
- Delivery
- Command and Control
- Installation
NIST
- DE.CM
CIS20
- CIS 13
CVE
| ID | Summary | CVSS |
|---|---|---|
| CVE-2023-36844 | 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.
| None | |
| CVE-2023-36845 | 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.
| None | |
| CVE-2023-36846 | A Missing Authentication for Critical Function vulnerability in Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause limited impact to the file system integrity. |
With a specific request to user.php that doesn't require authentication an attacker is able to upload arbitrary files via J-Web, leading to a loss of
integrity
for a certain
part of the file system, which may allow chaining to other vulnerabilities.
This issue affects Juniper Networks Junos OS on SRX Series:
- All versions prior to 20.4R3-S8;
- 21.1 versions 21.1R1 and later;
- 21.2 versions prior to 21.2R3-S6;
- 21.3 versions
prior to
21.3R3-S5;
- 21.4 versions
prior to
21.4R3-S5;
- 22.1 versions
prior to
22.1R3-S3;
- 22.2 versions
prior to
22.2R3-S2;
- 22.3 versions
prior to
22.3R2-S2, 22.3R3;
- 22.4 versions
prior to
22.4R2-S1, 22.4R3.
| None | |
| CVE-2023-36847 | A Missing Authentication for Critical Function vulnerability in Juniper Networks Junos OS on EX Series allows an unauthenticated, network-based attacker to cause limited impact to the file system integrity. |
With a specific request to installAppPackage.php that doesn't require authentication an attacker is able to upload arbitrary files via J-Web, leading to a loss of
integrity
for a certain
part of the file system, which may allow chaining to other vulnerabilities.
This issue affects Juniper Networks Junos OS on EX Series:
- All versions prior to 20.4R3-S8;
- 21.1 versions 21.1R1 and later;
- 21.2 versions prior to 21.2R3-S6;
- 21.3 versions
prior to
21.3R3-S5;
- 21.4 versions
prior to
21.4R3-S4;
- 22.1 versions
prior to
22.1R3-S3;
- 22.2 versions
prior to
22.2R3-S1;
- 22.3 versions
prior to
22.3R2-S2, 22.3R3;
- 22.4 versions
prior to
22.4R2-S1, 22.4R3.
| None |
Search
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| tstats count min(_time) as firstTime max(_time) as lastTime from datamodel=Web where Web.url IN ("*/webauth_operation.php?PHPRC=*") Web.status=200 by Web.http_user_agent, Web.status Web.http_method, Web.url, Web.url_length, Web.src, Web.dest, sourcetype
| `drop_dm_object_name("Web")`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `juniper_networks_remote_code_execution_exploit_detection_filter`
Macros
The SPL above uses the following Macros:
juniper_networks_remote_code_execution_exploit_detection_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Required fields
List of fields required to use this analytic.
- Web.http_user_agent
- Web.status
- Web.http_method
- Web.url
- Web.url_length
- Web.src
- Web.dest
- sourcetype
How To Implement
To implement this search, ensure that the Web data model is populated. The search is activated when the Web data model is accelerated. Network products, such as Suricata or Palo Alto, need to be mapped to the Web data model. Adjust the mapping as necessary to suit your specific products.
Known False Positives
Be aware of potential false positives - legitimate uses of the /webauth_operation.php endpoint may cause benign activities to be flagged.The URL in the analytic is specific to a successful attempt to exploit the vulnerability. Review contents of the HTTP body to determine if the request is malicious. If the request is benign, add the URL to the whitelist or continue to monitor.
Associated Analytic Story
RBA
| Risk Score | Impact | Confidence | Message |
|---|---|---|---|
| 72.0 | 90 | 80 | This analytic has identified a potential exploitation of a remote code execution vulnerability in Juniper Networks devices on $dest$ on the URL $url$ used for the exploit. |
Reference
- 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://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2023/CVE-2023-36844.yaml
- https://thehackernews.com/2023/08/new-juniper-junos-os-flaws-expose.html
- https://github.com/watchtowrlabs/juniper-rce_cve-2023-36844
- https://labs.watchtowr.com/cve-2023-36844-and-friends-rce-in-juniper-firewalls/
- https://vulncheck.com/blog/juniper-cve-2023-36845
Test Dataset
Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI.
Alternatively you can replay a dataset into a Splunk Attack Range
source | version: 1