CyberSecBulletin
CVE-2022-28716NVD status: Modified

BIG-IP: Improper Neutralization of Input During Web Page Generation

Published Updated By the CyberSecBulletin desk

CVE-2022-28716 is a high-severity improper neutralization of input during web page generation vulnerability in BIG-IP from F5, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists versions 16.1.2.2, 15.1.5.1, 14.1.4.6 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 0.76% chance of exploitation within 30 days, higher than 56% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update BIG-IP to 16.1.2.2 or 15.1.5.1 or 14.1.4.6 or 13.1.5, whichever matches your release line, or a later version.
  2. Update Big-ip Advanced Firewall Manager to 13.1.5 or 14.1.4.6 or 15.1.5.1 or 16.1.2.2, whichever matches your release line, or a later version.
  3. Update Big-ip Carrier-grade Nat to 13.1.5 or 14.1.4.6 or 15.1.5.1 or 16.1.2.2, whichever matches your release line, or a later version.
  4. Read the advisory on support.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.
  6. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
F5BIG-IP12.1.x; 11.6.x; 16.1.x up to, but not including, 16.1.2.2; 15.1.x up to, but not including, 15.1.5.1; 14.1.x up to, but not including, 14.1.4.6; 13.1.x up to, but not including, 13.1.516.1.2.2, 15.1.5.1, 14.1.4.6, 13.1.5
F5Big-ip Advanced Firewall Manager11.6.1 through 11.6.5; 12.1.0 through 12.1.6; 13.1.0 up to, but not including, 13.1.5; 14.1.0 up to, but not including, 14.1.4.6; 15.1.0 up to, but not including, 15.1.5.1; 16.1.0 up to, but not including, 16.1.2.213.1.5, 14.1.4.6, 15.1.5.1, 16.1.2.2
F5Big-ip Carrier-grade Nat11.6.1 through 11.6.5; 12.1.0 through 12.1.6; 13.1.0 up to, but not including, 13.1.5; 14.1.0 up to, but not including, 14.1.4.6; 15.1.0 up to, but not including, 15.1.5.1; 16.1.0 up to, but not including, 16.1.2.213.1.5, 14.1.4.6, 15.1.5.1, 16.1.2.2
F5Big-ip Policy Enforcement Manager11.6.1 through 11.6.5; 12.1.0 through 12.1.6; 13.1.0 up to, but not including, 13.1.5; 14.1.0 up to, but not including, 14.1.4.6; 15.1.0 up to, but not including, 15.1.5.1; 16.1.0 up to, but not including, 16.1.2.213.1.5, 14.1.4.6, 15.1.5.1, 16.1.2.2

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
RequiredA user must take an action such as opening a file or link.
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:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighCNA (f5.com)
CVSS 3.18.8HighNVD
CVSS 2.06.8MediumNVD

Official description

On 16.1.x versions prior to 16.1.2.2, 15.1.x versions prior to 15.1.5.1, 14.1.x versions prior to 14.1.4.6, 13.1.x versions prior to 13.1.5, and all versions of 12.1.x 11.6.x, a DOM-based cross-site scripting (XSS) vulnerability exists in an undisclosed page of the BIG-IP AFM, CGNAT, and PEM Configuration utility that allows an attacker to execute JavaScript in the context of the currently logged-in user. 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: Improper Neutralization of Input During Web Page Generation

The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

How developers prevent this class of flaw

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and Apache Wicket.
  • Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Improper Neutralization of Input During Web Page Generation vulnerabilities (CWE-79)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in BIG-IP

All BIG-IP vulnerabilities

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