CyberSecBulletin
CVE-2024-27127NVD status: Modified

QTS: Double Free

CVE-2024-27127 is a high-severity double free vulnerability in QTS from QNAP, with a CVSS 3.1 base score of 8.8 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. The record lists version 5.1.7.2770 build 20240520 as the first without the flaw, so updating QTS to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.7% chance of exploitation within 30 days, higher than 54% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update QTS to 5.1.7.2770 build 20240520 or a later version.
  2. Update QuTS hero to h5.1.7.2770 build 20240520 or a later version.
  3. Read the advisory on qnap.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
QNAPQTS5.1.x up to, but not including, 5.1.7.2770 build 20240520; 5.1.x5.1.7.2770 build 20240520
QNAPQuTS heroh5.1.x up to, but not including, h5.1.7.2770 build 20240520; h5.1.xh5.1.7.2770 build 20240520

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
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.17.2HighCNA (qnapsecurity.com.tw)
CVSS 3.18.8HighNVD

Official description

A double free vulnerability has been reported to affect several QNAP operating system versions. If exploited, the vulnerability could allow authenticated users to execute arbitrary code via a network. We have already fixed the vulnerability in the following version: QTS 5.1.7.2770 build 20240520 and later QuTS hero h5.1.7.2770 build 20240520 and later

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

The underlying weakness: Double Free

The product calls free() twice on the same memory address.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
  • Use a static analysis tool to find double free instances.

More Double Free vulnerabilities (CWE-415)

Timeline

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

References

Other vulnerabilities in QTS

All QTS vulnerabilities

Recent Double Free vulnerabilities

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