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CVE-2026-58595NVD status: Analyzed

Microsoft Bing Search for iOS: Improper Restriction of Rendered UI Layers or Frames

CVE-2026-58595 is a high-severity improper restriction of rendered UI layers or frames vulnerability in Microsoft Bing Search for iOS from Microsoft, 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, but only if a user takes part, for example by opening a link or file. The record lists version 33.4.440529002 as the first without the flaw, so updating Microsoft Bing Search for iOS to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.69% chance of exploitation within 30 days, higher than 53% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Microsoft Bing Search for iOS to 33.4.440529002 or a later version.
  2. Update Bing Search to 33.4.440529002 or a later version.
  3. Read the advisory on msrc.microsoft.com for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  5. 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
MicrosoftMicrosoft Bing Search for iOS1.0 up to, but not including, 33.4.44052900233.4.440529002
MicrosoftBing Searchbefore 33.4.44052900233.4.440529002

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
NoneNo data is disclosed.
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:N/I:H/A:H. Scored by CNA (microsoft.com).

Official description

Improper restriction of rendered ui layers or frames in Microsoft Bing App for IOS allows an unauthorized attacker to perform spoofing over a network.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Restriction of Rendered UI Layers or Frames

The web application does not restrict or incorrectly restricts frame objects or UI layers that belong to another application or domain.

How developers prevent this class of flaw

  • Use the frame-ancestors directive in the Content Security Policy, which is intended to define restrictions when it comes to allowing embedded content.
  • The use of X-Frame-Options (now partially obsolete as of September 2026) allows developers of web content to restrict the usage of their application within the form of overlays, frames, or iFrames. The developer can indicate from which domains can frame the content. The concept of X-Frame-Options is well documented, but implementation of this protection mechanism is in development to cover gaps; often, there is a need for allowing frames from multiple domains.
  • Use a frame-breaker script in each page that should not be framed. This is very helpful for legacy browsers that do not support the X-Frame-Options security feature previously mentioned (which is now partially obsolete).

More Improper Restriction of Rendered UI Layers or Frames vulnerabilities (CWE-1021)

Timeline

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

References

Recent Improper Restriction of Rendered UI Layers or Frames vulnerabilities

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