CVE-2026-42781 (GCVE-0-2026-42781)

Vulnerability from cvelistv5 – Published: 2026-05-13 14:12 – Updated: 2026-05-13 16:15
VLAI?
Title
BIG-IP FastL4 virtual server vulnerability
Summary
When embedded Packet Velocity Acceleration (ePVA) acceleration is configured, undisclosed local ethernet traffic can cause an increase in ePVA and Traffic Management Microkernel (TMM) resource utilization.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Severity ?
6.5 (Medium)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.1 (High)
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
  • CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
f5
References
URL Tags
https://my.f5.com/manage/s/article/K000160862 vendor-advisorypatch
Impacted products
Vendor Product Version
F5 BIG-IP Unaffected: 21.1.0 , < * (custom)
Affected: 21.0.0 , < 21.0.0.1 (custom)
Affected: 17.5.0 , < 17.5.1.4 (custom)
Affected: 17.1.0 , < 17.1.3.1 (custom)
Unaffected: 16.1.0 , < * (custom)
Create a notification for this product.
Date Public ?
2026-05-13 14:00
Credits
F5
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.