CyberSecBulletin
CVE-2023-39954NVD status: Modified

security-advisories: Missing Encryption of Sensitive Data

CVE-2023-39954 is a high-severity missing encryption of sensitive data vulnerability in security-advisories from Nextcloud, with a CVSS 3.1 base score of 8.1 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 security-advisories versions: >= 1.0.0, < 1.3.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.44% 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. Update User Oidc to 1.3.3 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Nextcloudsecurity-advisories>= 1.0.0, < 1.3.3Not stated
NextcloudUser Oidc1.0.0 up to, but not including, 1.3.31.3.3

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
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
NoneAvailability is not affected.

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

Scoring systemScoreSeverityScored by
CVSS 3.13.8LowCNA (github.com)
CVSS 3.18.1HighNVD

Official description

user_oidc provides the OIDC connect user backend for Nextcloud, an open-source cloud platform. Starting in version 1.0.0 and prior to version 1.3.3, an attacker that obtained at least read access to a snapshot of the database can impersonate the Nextcloud server towards linked servers. user_oidc 1.3.3 contains a patch. No known workarounds are available.

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

The underlying weakness: Missing Encryption of Sensitive Data

The product does not encrypt sensitive or critical information before storage or transmission.

How developers prevent this class of flaw

  • Clearly specify which data or resources are valuable enough that they should be protected by encryption. Require that any transmission or storage of this data/resource should use well-vetted encryption algorithms.
  • 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.
  • When using industry-approved techniques, use them correctly. Don't cut corners by skipping resource-intensive steps (CWE-325). These steps are often essential for preventing common attacks.

More Missing Encryption of Sensitive Data vulnerabilities (CWE-311)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other references

Other vulnerabilities in security-advisories

All security-advisories vulnerabilities

Recent Missing Encryption of Sensitive Data vulnerabilities

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