CVE-2021-34346
CVE-2021-34346 is a critical-severity vulnerability in Qnap Nvr Storage Expansion Firmware with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 2% (73rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Qnap Nvr Storage Expansion Firmware
- Published:
- Last modified:
Description
A stack buffer overflow vulnerability has been reported to affect QNAP device running NVR Storage Expansion. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of NVR Storage Expansion: NVR Storage Expansion 1.0.6 ( 2021/08/03 ) and later
Frequently asked questions
- What is CVE-2021-34346?
- A stack buffer overflow vulnerability has been reported to affect QNAP device running NVR Storage Expansion. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of NVR Storage Expansion: NVR Storage Expansion 1.0.6 ( 2021/08/03 ) and later
- How severe is CVE-2021-34346?
- CVE-2021-34346 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-34346 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-34346?
- CVE-2021-34346 affects Qnap Nvr Storage Expansion Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-34346?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-34346 published?
- CVE-2021-34346 was published on 2021-09-10 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:qnap:nvr_storage_expansion_firmware:*:*:*:*:*:*:*:*
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