CyberSecBulletin
CVE-2023-40537NVD status: Modified

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Published Updated By the CyberSecBulletin desk

CVE-2023-40537 is a high-severity vulnerability in BIG-IP from F5, with a CVSS 3.1 base score of 8.1 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 16.1.4, 15.1.9 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 0.55% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update BIG-IP to 16.1.4 or 15.1.9, whichever matches your release line, or a later version.
  2. Update Big-ip Access Policy Manager to 15.1.9 or 16.1.4, whichever matches your release line, or a later version.
  3. Update Big-ip Advanced Firewall Manager to 15.1.9 or 16.1.4, whichever matches your release line, or a later version.
  4. Read the advisory on my.f5.com for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
F5BIG-IP16.1.0 up to, but not including, 16.1.4; 15.1.0 up to, but not including, 15.1.9; 14.1.0 and later; 13.1.0 and later16.1.4, 15.1.9
F5Big-ip Access Policy Manager13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Advanced Firewall Manager13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Application Security Manager13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Domain Name System13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Local Traffic Manager13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Advanced Web Application Firewall13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Analytics13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Application Acceleration Manager13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Application Visibility And Reporting13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Carrier-grade Nat13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Ddos Hybrid Defender13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Fraud Protection Service13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Global Traffic Manager13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Link Controller13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Policy Enforcement Manager13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip SSL Orchestrator13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Webaccelerator13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4
F5Big-ip Websafe13.1.0 through 14.1.5; 15.1.0 up to, but not including, 15.1.9; 16.1.0 up to, but not including, 16.1.415.1.9, 16.1.4

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
HighSuccess depends on conditions outside the attacker's control.
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
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (f5.com).

Official description

An authenticated user's session cookie may remain valid for a limited time after logging out from the BIG-IP Configuration utility on a multi-blade VIPRION platform. 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.

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in BIG-IP

All BIG-IP vulnerabilities

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