CVE-2026-40061: CWE-77 Improper Neutralization of Special Elements used in a Command ('Command Injection') in F5 BIG-IP
CVE-2026-40061 is a command injection vulnerability in F5 BIG-IP DNS when provisioned, affecting certain versions. It allows an authenticated user with Resource Administrator or Administrator roles to execute arbitrary system commands with elevated privileges. In Appliance mode deployments, exploitation can cross a security boundary. The vulnerability has a CVSS score of 6.5, indicating medium severity. No official patch or remediation level has been provided yet, and no known exploits are reported in the wild.
AI Analysis
Technical Summary
This vulnerability exists in an undisclosed iControl REST and BIG-IP TMOS Shell (tmsh) command within F5 BIG-IP DNS. An authenticated attacker with sufficient privileges (Resource Administrator or Administrator) can leverage improper neutralization of special elements (CWE-77) to execute arbitrary system commands with higher privileges. This can lead to privilege escalation and potential security boundary crossing in Appliance mode deployments. Affected versions include 16.1.0, 17.1.0, 17.5.0, and 21.0.0. The CVSS 3.1 base score is 6.5 (AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N), reflecting network attack vector, low attack complexity, high privileges required, no user interaction, unchanged scope, and high confidentiality and integrity impact with no availability impact. No patch or official remediation guidance is currently available.
Potential Impact
An authenticated attacker with Resource Administrator or Administrator privileges can execute arbitrary system commands with elevated privileges, potentially leading to unauthorized control over the system and crossing security boundaries in Appliance mode. This compromises confidentiality and integrity of the affected system. There are no known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, restrict Resource Administrator and Administrator role access to trusted personnel only and monitor for unusual activity related to iControl REST and tmsh commands. Follow F5's official advisories for updates.
CVE-2026-40061: CWE-77 Improper Neutralization of Special Elements used in a Command ('Command Injection') in F5 BIG-IP
Description
CVE-2026-40061 is a command injection vulnerability in F5 BIG-IP DNS when provisioned, affecting certain versions. It allows an authenticated user with Resource Administrator or Administrator roles to execute arbitrary system commands with elevated privileges. In Appliance mode deployments, exploitation can cross a security boundary. The vulnerability has a CVSS score of 6.5, indicating medium severity. No official patch or remediation level has been provided yet, and no known exploits are reported in the wild.
CVSS v3.1
Score 6.5medium
Affected software
pkg:github/f5/BIG-IPRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability exists in an undisclosed iControl REST and BIG-IP TMOS Shell (tmsh) command within F5 BIG-IP DNS. An authenticated attacker with sufficient privileges (Resource Administrator or Administrator) can leverage improper neutralization of special elements (CWE-77) to execute arbitrary system commands with higher privileges. This can lead to privilege escalation and potential security boundary crossing in Appliance mode deployments. Affected versions include 16.1.0, 17.1.0, 17.5.0, and 21.0.0. The CVSS 3.1 base score is 6.5 (AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N), reflecting network attack vector, low attack complexity, high privileges required, no user interaction, unchanged scope, and high confidentiality and integrity impact with no availability impact. No patch or official remediation guidance is currently available.
Potential Impact
An authenticated attacker with Resource Administrator or Administrator privileges can execute arbitrary system commands with elevated privileges, potentially leading to unauthorized control over the system and crossing security boundaries in Appliance mode. This compromises confidentiality and integrity of the affected system. There are no known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, restrict Resource Administrator and Administrator role access to trusted personnel only and monitor for unusual activity related to iControl REST and tmsh commands. Follow F5's official advisories for updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- f5
- Date Reserved
- 2026-04-30T23:04:10.862Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a049708cbff5d8610dff471
Added to database: 05/13/2026, 15:21:44 UTC
Last enriched: 05/20/2026, 18:58:06 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 51
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