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CVE-2023-28161NVD status: Modified

Firefox: Improper Preservation of Permissions

CVE-2023-28161 is a high-severity improper preservation of permissions vulnerability in Firefox from Mozilla, 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 version 111 as the first without the flaw, so updating Firefox to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.62% chance of exploitation within 30 days, higher than 51% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Firefox to 111 or a later version.
  2. Read the advisory on bugzilla.mozilla.org for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  4. 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
MozillaFirefoxbefore 111111

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 3.18.8HighNVD
CVSS 3.18.8HighCISA (ADP)

Official description

If temporary "one-time" permissions, such as the ability to use the Camera, were granted to a document loaded using a file: URL, that permission persisted in that tab for all other documents loaded from a file: URL. This is potentially dangerous if the local files came from different sources, such as in a download directory. This vulnerability affects Firefox < 111.

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

The underlying weakness: Improper Preservation of Permissions

The product does not preserve permissions or incorrectly preserves permissions when copying, restoring, or sharing objects, which can cause them to have less restrictive permissions than intended.

More Improper Preservation of Permissions vulnerabilities (CWE-281)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Firefox

All Firefox vulnerabilities

Recent Improper Preservation of Permissions vulnerabilities

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