CyberSecBulletin
CVE-2023-5256NVD status: Modified

Core: Exposure of Sensitive Information to an Unauthorized Actor

Published Updated By the CyberSecBulletin desk

CVE-2023-5256 is a high-severity exposure of sensitive information to an unauthorized actor vulnerability in Core from Drupal, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Core versions: 10.1 through 10.1.4; 10.0 through 10.0.11; 9.5 through 9.5.11. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.85% chance of exploitation within 30 days, higher than 59% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update drupal to 10.1.4 or 10.0.11 or 9.5.11, whichever matches your release line, or a later version.
  2. Read the advisory on drupal.org for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
DrupalCore10.1 through 10.1.4; 10.0 through 10.0.11; 9.5 through 9.5.11Not stated
Drupaldrupal10.1 up to, but not including, 10.1.4; 10.0 up to, but not including, 10.0.11; 9.5 up to, but not including, 9.5.1110.1.4, 10.0.11, 9.5.11

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
HighSuccess depends on conditions outside the attacker's control.
Privileges required
LowA basic user account is enough.
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:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighNVD
CVSS 3.17.5HighCISA (ADP)

Official description

In certain scenarios, Drupal's JSON:API module will output error backtraces. With some configurations, this may cause sensitive information to be cached and made available to anonymous users, leading to privilege escalation. This vulnerability only affects sites with the JSON:API module enabled, and can be mitigated by uninstalling JSON:API. The core REST and contributed GraphQL modules are not affected.

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

The underlying weakness: Exposure of Sensitive Information to an Unauthorized Actor

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

How developers prevent this class of flaw

  • Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

More Exposure of Sensitive Information to an Unauthorized Actor vulnerabilities (CWE-200)

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 Core

All Core vulnerabilities

Recent Exposure of Sensitive Information to an Unauthorized Actor vulnerabilities

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