F5-K000158115: Medium severity F5 BIG-IP vulnerability

Published Dec 9, 2025
·
Updated

libexpat in Expat before 2.7.2 allows attackers to trigger large dynamic memory allocations via a small document that is submitted for parsing.

Affected Software

6 affected components
F5 BIG-IP=21.0.0
F5 BIG-IP>=17.5.0<=17.5.1, >=17.1.0<=17.1.3
F5 BIG-IP>=16.1.0<=16.1.6
F5 BIG-IP>=15.1.0<=15.1.10
F5 F5OS-A>=1.8.0<=1.8.3, >=1.5.1<=1.5.4
F5 F5OS-C>=1.8.0<=1.8.2, >=1.6.0<=1.6.4

Event History

Dec 9, 2025
Advisory Published
via F5·03:43 PM
Data Sourced
via F5·03:43 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of F5-K000158115?

The severity of F5-K000158115 is considered high due to the potential for attackers to exploit large memory allocations.

2

How do I fix F5-K000158115?

To fix F5-K000158115, upgrade to the latest version of Expat that resolves this vulnerability.

3

What versions are affected by F5-K000158115?

F5-K000158115 affects F5 BIG-IP versions 15.1.0 through 15.1.10, 16.1.0 through 16.1.6, 17.1.0 through 17.1.3, 17.5.0 through 17.5.1, and F5OS versions 1.5.1 through 1.5.4 and 1.8.0 through 1.8.3.

4

Can F5-K000158115 be exploited remotely?

Yes, F5-K000158115 can be exploited remotely, which increases its risk profile significantly.

5

What are the potential impacts of F5-K000158115?

The potential impacts of F5-K000158115 include denial of service and resource exhaustion due to excessive memory allocations.

Contact

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