CVE-2026-40067: CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') in F5 BIG-IP
When a BIG-IP APM access policy is configured on a virtual server, undisclosed traffic can cause the apmd process to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-40067) in F5 BIG-IP arises from a classic buffer overflow (CWE-120) in the apmd process triggered when an APM access policy is configured on a virtual server. Specifically, certain undisclosed traffic can cause the apmd process to terminate unexpectedly. The issue affects several versions of BIG-IP, including 21.0.0, 17.5.0, 17.1.0, and 16.1.0. The CVSS 3.1 base score is 7.5, reflecting a network attack vector with no required privileges or user interaction, and results in high impact on availability. No patch or official remediation guidance has been published yet, and the vulnerability is not related to cloud services.
Potential Impact
Successful exploitation causes the apmd process on BIG-IP devices to terminate, resulting in denial of service. There is no indication of confidentiality or integrity impact. The vulnerability can be triggered remotely without authentication or user interaction.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, monitor vendor communications for updates. No official mitigation or workaround is currently documented.
CVE-2026-40067: CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') in F5 BIG-IP
Description
When a BIG-IP APM access policy is configured on a virtual server, undisclosed traffic can cause the apmd process to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-40067) in F5 BIG-IP arises from a classic buffer overflow (CWE-120) in the apmd process triggered when an APM access policy is configured on a virtual server. Specifically, certain undisclosed traffic can cause the apmd process to terminate unexpectedly. The issue affects several versions of BIG-IP, including 21.0.0, 17.5.0, 17.1.0, and 16.1.0. The CVSS 3.1 base score is 7.5, reflecting a network attack vector with no required privileges or user interaction, and results in high impact on availability. No patch or official remediation guidance has been published yet, and the vulnerability is not related to cloud services.
Potential Impact
Successful exploitation causes the apmd process on BIG-IP devices to terminate, resulting in denial of service. There is no indication of confidentiality or integrity impact. The vulnerability can be triggered remotely without authentication or user interaction.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, monitor vendor communications for updates. No official mitigation or workaround is currently documented.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- f5
- Date Reserved
- 2026-04-30T23:02:33.947Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a049708cbff5d8610dff474
Added to database: 5/13/2026, 3:21:44 PM
Last enriched: 5/13/2026, 4:06:37 PM
Last updated: 5/14/2026, 6:51:37 AM
Views: 2
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