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CVE-2024-45368NVD status: Deferred

DirectLogic H2-DM1E: Session Fixation

CVE-2024-45368 is a high-severity session fixation vulnerability in DirectLogic H2-DM1E from AutomationDirect, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. Affected DirectLogic H2-DM1E versions: 2.8.0 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.34% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of DirectLogic H2-DM1E you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
AutomationDirectDirectLogic H2-DM1E2.8.0 and earlierNot stated
Automationdirecth2-dm1e_firmware2.8.0 and earlierNot 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
AdjacentThe attacker must be on the same local network segment.
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
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (hq.dhs.gov).

Scoring systemScoreSeverityScored by
CVSS 4.08.7HighCNA (hq.dhs.gov)
CVSS 3.18.8HighCNA (hq.dhs.gov)

Official description

The H2-DM1E PLC's authentication protocol appears to utilize either a custom encoding scheme or a challenge-response protocol. However, there's an observed anomaly in the H2-DM1E PLC's protocol execution, namely its acceptance of multiple distinct packets as valid authentication responses. This behavior deviates from standard security practices where a single, specific response or encoding pattern is expected for successful authentication.

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

The underlying weakness: Session Fixation

Authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions.

How developers prevent this class of flaw

  • Invalidate any existing session identifiers prior to authorizing a new user session.
  • For platforms such as ASP that do not generate new values for sessionid cookies, utilize a secondary cookie. In this approach, set a secondary cookie on the user's browser to a random value and set a session variable to the same value. If the session variable and the cookie value ever don't match, invalidate the session, and force the user to log on again.
  • Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.

More Session Fixation vulnerabilities (CWE-384)

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 DirectLogic H2-DM1E

All DirectLogic H2-DM1E vulnerabilities

Recent Session Fixation vulnerabilities

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