BIG-IP: Uncontrolled Recursion
CVE-2025-54858 is a high-severity uncontrolled recursion vulnerability in BIG-IP from F5, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 17.5.1.3, 17.1.3, 16.1.6.1 as the first without the flaw, so updating BIG-IP to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.35% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update BIG-IP to 17.5.1.3 or 17.1.3 or 16.1.6.1 or 15.1.10.8, whichever matches your release line, or a later version.
- Update Big-ip Advanced Web Application Firewall to 15.1.10.8 or 16.1.6.1 or 17.1.3 or 17.5.1.3, whichever matches your release line, or a later version.
- Update Big-ip Application Security Manager to 15.1.10.8 or 16.1.6.1 or 17.1.3 or 17.5.1.3, whichever matches your release line, or a later version.
- Read the advisory on my.f5.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| F5 | BIG-IP | 17.5.0 up to, but not including, 17.5.1.3; 17.1.0 up to, but not including, 17.1.3; 16.1.0 up to, but not including, 16.1.6.1; 15.1.0 up to, but not including, 15.1.10.8 | 17.5.1.3, 17.1.3, 16.1.6.1, 15.1.10.8 |
| F5 | Big-ip Advanced Web Application Firewall | 15.1.0 up to, but not including, 15.1.10.8; 16.1.0 up to, but not including, 16.1.6.1; 17.1.0 up to, but not including, 17.1.3; 17.5.0 up to, but not including, 17.5.1.3 | 15.1.10.8, 16.1.6.1, 17.1.3, 17.5.1.3 |
| F5 | Big-ip Application Security Manager | 15.1.0 up to, but not including, 15.1.10.8; 16.1.0 up to, but not including, 16.1.6.1; 17.1.0 up to, but not including, 17.1.3; 17.5.0 up to, but not including, 17.5.1.3 | 15.1.10.8, 16.1.6.1, 17.1.3, 17.5.1.3 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA (f5.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.7 | High | CNA (f5.com) |
| CVSS 3.1 | 7.5 | High | CNA (f5.com) |
Official description
When a BIG-IP Advanced WAF or BIG-IP ASM Security Policy is configured with a JSON content profile that has a malformed JSON schema, and the security policy is applied to a virtual server, undisclosed requests can cause the bd process to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Uncontrolled Recursion
The product does not properly control the amount of recursion that takes place, consuming excessive resources, such as allocated memory or the program stack.
How developers prevent this class of flaw
- Ensure that an end condition will be reached under all logic conditions. The end condition may include checking against the depth of recursion and exiting with an error if the recursion goes too deep. The complexity of the end condition contributes to the effectiveness of this action.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in BIG-IP
- 9.8 Critical severity
F5 BIG-IP APM Heap-based Buffer Overflow Exploited
- 8.8 High severity
- 7.5 High severity
- 8.7 High severity
- 8.7 High severity
- 7.5 High severity
Recent Uncontrolled Recursion vulnerabilities
- 7.5 High severity
- 8.6 High severity
- 7.5 High severity
- 7.8 High severity
- 7.5 High severity
- 7.5 High severity
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