CyberSecBulletin
CVE-2025-4211NVD status: Deferred

Qt: Improper Link Resolution Before File Access

CVE-2025-4211 is a high-severity improper link resolution before file access vulnerability in Qt, with a CVSS 4.0 base score of 7.3 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, but only if a user takes part, for example by opening a link or file. Affected Qt versions: 5.15.18 and earlier; 6.0.0 through 6.5.8; 6.6.0 through 6.8.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.21% 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 Qt you run against the affected versions below, and install the vendor's latest release.
  2. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
QtQt5.15.18 and earlier; 6.0.0 through 6.5.8; 6.6.0 through 6.8.1Not 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
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Attack requirements
PresentThe target must be in a specific state or configuration for the attack to work.
Privileges required
LowA basic user account is enough.
User interaction
PassiveA user only needs to do something routine, such as viewing a page.
Confidentiality (vulnerable system)
HighSerious loss of confidentiality on the vulnerable system.
Integrity (vulnerable system)
HighSerious loss of integrity on the vulnerable system.
Availability (vulnerable system)
HighSerious loss of availability on the vulnerable system.
Confidentiality (other systems)
HighSerious loss of confidentiality on systems beyond the vulnerable one.
Integrity (other systems)
HighSerious loss of integrity on systems beyond the vulnerable one.
Availability (other systems)
HighSerious loss of availability on systems beyond the vulnerable one.

Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:P/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA.

Official description

Improper Link Resolution Before File Access ('Link Following') vulnerability in QFileSystemEngine in the Qt corelib module on Windows which potentially allows Symlink Attacks and the use of Malicious Files. Issue originates from CVE-2024-38081. The vulnerability arises from the use of the GetTempPath API, which can be exploited by attackers to manipulate temporary file paths, potentially leading to unauthorized access and privilege escalation. The affected public API in the Qt Framework is QDir::tempPath() and anything that uses it, such as QStandardPaths with TempLocation, QTemporaryDir, and QTemporaryFile. This issue affects all version of Qt up to and including 5.15.18, from 6.0.0 through 6.5.8, from 6.6.0 through 6.8.1. It is fixed in Qt 5.15.19, Qt 6.5.9, Qt 6.8.2, 6.9.0

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

The underlying weakness: Improper Link Resolution Before File Access

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

How developers prevent this class of flaw

  • Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

More Improper Link Resolution Before File Access vulnerabilities (CWE-59)

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 Qt

All Qt vulnerabilities

Recent Improper Link Resolution Before File Access vulnerabilities

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