CyberSecBulletin
CVE-2023-6971NVD status: Modified

Backup Migration: Inclusion of Functionality from Untrusted Control Sphere

CVE-2023-6971 is a critical-severity inclusion of functionality from untrusted control sphere vulnerability in Backup Migration from Migrate, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Backup Migration versions: 1.0.8 through 1.3.9. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 6.42% chance of exploitation within 30 days, which is in the top 6.2% of all scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Backup Migration you run against the affected versions below, and install the vendor's latest release.
  2. 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
MigrateBackup Migration1.0.8 through 1.3.9Not 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
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.18.1HighCNA (wordfence.com)
CVSS 3.19.8CriticalNVD

Official description

The Backup Migration plugin for WordPress is vulnerable to Remote File Inclusion in versions 1.0.8 to 1.3.9 via the 'content-dir' HTTP header. This makes it possible for unauthenticated attackers to include remote files on the server, resulting in code execution. NOTE: Successful exploitation of this vulnerability requires that the target server's php.ini is configured with 'allow_url_include' set to 'on'. This feature is deprecated as of PHP 7.4 and is disabled by default, but can still be explicitly enabled in later versions of PHP.

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

The underlying weakness: Inclusion of Functionality from Untrusted Control Sphere

The product imports, requires, or includes executable functionality (such as a library) from a source that is outside of the intended control sphere.

How developers prevent this class of flaw

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
  • When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs. For example, ID 1 could map to inbox.txt and ID 2 could map to profile.txt. Features such as the ESAPI AccessReferenceMap provide this capability.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Inclusion of Functionality from Untrusted Control Sphere vulnerabilities (CWE-829)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Recent Inclusion of Functionality from Untrusted Control Sphere vulnerabilities

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