CyberSecBulletin
CVE-2023-41677NVD status: Modified

FortiOS: Insufficiently Protected Credentials

CVE-2023-41677 is a high-severity insufficiently protected credentials vulnerability in FortiOS from Fortinet, 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. Affected FortiOS versions: 7.4.0 through 7.4.1; 7.2.0 through 7.2.6; 7.0.0 through 7.0.12, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.75% 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. Check which version of FortiOS 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.
  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
FortinetFortiOS7.4.0 through 7.4.1; 7.2.0 through 7.2.6; 7.0.0 through 7.0.12; 6.4.0 through 6.4.14; 6.2.0 through 6.2.15; 6.0.0 through 6.0.18Not stated
FortinetFortiProxy7.4.0 through 7.4.1; 7.2.0 through 7.2.7; 7.0.0 through 7.0.13; 2.0.0 through 2.0.14; 1.2.1 through 1.2.13; 01.02.00; 1.1.4 through 1.1.6; 01.01.00 through 01.01.03; and 4 more rangesNot 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
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 (fortinet.com)
CVSS 3.18.8HighNVD

Official description

A insufficiently protected credentials vulnerability in Fortinet FortiOS 7.4.0 through 7.4.1, FortiOS 7.2.0 through 7.2.6, FortiOS 7.0.0 through 7.0.12, FortiOS 6.4.0 through 6.4.14, FortiOS 6.2.0 through 6.2.15, FortiOS 6.0 all versions, FortiProxy 7.4.0 through 7.4.1, FortiProxy 7.2.0 through 7.2.7, FortiProxy 7.0.0 through 7.0.13, FortiProxy 2.0 all versions, FortiProxy 01.02 all versions, FortiProxy 1.2 all versions, FortiProxy 01.01 all versions, FortiProxy 1.1 all versions, FortiProxy 01.00 all versions allows attacker to execute unauthorized code or commands via targeted social engineering attack

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

The underlying weakness: Insufficiently Protected Credentials

The product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval.

How developers prevent this class of flaw

  • Use an appropriate security mechanism to protect the credentials.
  • Make appropriate use of cryptography to protect the credentials.
  • Use industry standards to protect the credentials (e.g. LDAP, keystore, etc.).

More Insufficiently Protected Credentials vulnerabilities (CWE-522)

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 FortiOS

All FortiOS vulnerabilities

Recent Insufficiently Protected Credentials vulnerabilities

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