CyberSecBulletin
CVE-2026-110907NVD status: Awaiting Analysis

Backdrop: Incorrect Resource Transfer Between Spheres

CVE-2026-110907 is a high-severity incorrect resource transfer between spheres vulnerability in Backdrop from BackdropCMS, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 1.35.2, 1.34.6 as the first without the flaw, so updating Backdrop to one of those releases or later removes the exposure. 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. Update Backdrop to 1.35.2 or 1.34.6, whichever matches your release line, or a later version.
  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
BackdropCMSBackdrop1.35.0 up to, but not including, 1.35.2; 1.34.0 up to, but not including, 1.34.61.35.2, 1.34.6

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
NoneNothing can be modified.
Availability
NoneAvailability is not affected.

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

Official description

Backdrop CMS Core 1.35.x before 1.35.2 and 1.34.x before 1.34.6 mishandles tokens. A token is a small placeholder string (like [node:title] or [user:name]) used to automatically insert dynamic data into text. A browser is provided for selecting tokens by type. The product doesn't sufficiently limit access to the types of tokens that are available in the token browser. The names of the individual tokens are adequately protected.

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

The underlying weakness: Incorrect Resource Transfer Between Spheres

The product does not properly transfer a resource/behavior to another sphere, or improperly imports a resource/behavior from another sphere, in a manner that provides unintended control over that resource.

More Incorrect Resource Transfer Between Spheres vulnerabilities (CWE-669)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Backdrop

All Backdrop vulnerabilities

Recent Incorrect Resource Transfer Between Spheres vulnerabilities

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