CyberSecBulletin
CVE-2023-41273NVD status: Modified

QTS: Out-of-bounds Write

CVE-2023-41273 is a high-severity out-of-bounds write vulnerability in QTS from QNAP, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. The record lists version 5.1.2.2533 build 20230926 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 0.56% 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 QTS to 5.1.2.2533 build 20230926 or a later version.
  2. Update QuTS hero to h5.1.2.2534 build 20230927 or a later version.
  3. Update QuTScloud to c5.1.5.2651 or a later version.
  4. 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, 5.1.2.2533 build 202309265.1.2.2533 build 20230926
QNAPQuTS heroh5.1.x up to, but not including, h5.1.2.2534 build 20230927h5.1.2.2534 build 20230927
QNAPQuTScloudc5.x.x up to, but not including, c5.1.5.2651c5.1.5.2651

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
HighAdministrator-level access is required first.
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:H/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.15.5MediumCNA (qnapsecurity.com.tw)
CVSS 3.17.2HighNVD

Official description

A heap-based buffer overflow vulnerability has been reported to affect several QNAP operating system versions. If exploited, the vulnerability could allow authenticated administrators to execute code via a network. We have already fixed the vulnerability in the following versions: QTS 5.1.2.2533 build 20230926 and later QuTS hero h5.1.2.2534 build 20230927 and later QuTScloud c5.1.5.2651 and later

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

The underlying weakness: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

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 vulnerabilities in QTS

All QTS vulnerabilities

Recent Out-of-bounds Write vulnerabilities

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