CyberSecBulletin
CVE-2023-25603NVD status: Modified

FortiDDoS-F: Permissive Cross-domain Security Policy with Untrusted Domains

CVE-2023-25603 is a critical-severity permissive cross-domain security policy with untrusted domains vulnerability in FortiDDoS-F from Fortinet, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected FortiDDoS-F versions: 6.4.0 through 6.4.1; 6.3.0 through 6.3.4. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.4% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of FortiDDoS-F you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on fortiguard.com 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.

Affected products and versions

VendorProductAffected versionsFixed in
FortinetFortiDDoS-F6.4.0 through 6.4.1; 6.3.0 through 6.3.4Not stated
FortinetFortiADC7.1.0 through 7.1.1Not stated

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
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
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.15.4MediumCNA (fortinet.com)
CVSS 3.19.1CriticalNVD

Official description

A permissive cross-domain policy with untrusted domains vulnerability in Fortinet FortiADC 7.1.0 - 7.1.1, FortiDDoS-F 6.3.0 - 6.3.4 and 6.4.0 - 6.4.1 allow an unauthorized attacker to carry out privileged actions and retrieve sensitive information via crafted web requests.

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

The underlying weakness: Permissive Cross-domain Security Policy with Untrusted Domains

The product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate.

How developers prevent this class of flaw

  • Define a restrictive Content Security Policy or cross-domain policy file.
  • Avoid using wildcards in the CSP / cross-domain policy file. Any domain matching the wildcard expression will be implicitly trusted, and can perform two-way interaction with the target server.
  • For Flash, modify crossdomain.xml to use meta-policy options such as 'master-only' or 'none' to reduce the possibility of an attacker planting extraneous cross-domain policy files on a server.

More Permissive Cross-domain Security Policy with Untrusted Domains vulnerabilities (CWE-942)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in FortiDDoS-F

All FortiDDoS-F vulnerabilities

Recent Permissive Cross-domain Security Policy with Untrusted Domains vulnerabilities

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