Security Resilience

CVE-2023-28997

Nextcloud Desktop 3.0.0 – 3.6.5

Public PoC
Published
04 April 2023
Modified
03 November 2025
Patch / advisory
View advisory
CVSS Score v3.1 6.7
Click a component to see what it means
Raw vectorCVSS:3.1/AV:P/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:N
EPSS Score 0.011 65th percentile
Risk Priority 51 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-28997 is a medium-severity Reusing a Nonce, Key Pair in Encryption (CWE-323) vulnerability in Nextcloud Desktop. Its CVSS base score is 6.7 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data Obfuscation (T1001); ranked in the top 35% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

OWASP Top 10 for Web (2025)

A04:2025 Cryptographic Failures

EU & UK References

Vulnerability Data

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server. Starting with version 3.0.0 and prior to version 3.6.5, a malicious server administrator can recover and modify the contents of end-to-end encrypted files. Users should upgrade the…

more

Nextcloud Desktop client to 3.6.5 to receive a patch. No known workarounds are available.

CWE(s)
CWE-323

Related Threats

MITRE ATT&CK Enterprise Techniques

T1001 Data Obfuscation Command And Control
Adversaries may obfuscate command and control traffic to make it more difficult to detect.
attack.mitre.org →
T1003.001 LSASS Memory Credential Access
Adversaries may attempt to access credential material stored in the process memory of the Local Security Authority Subsystem Service (LSASS).
attack.mitre.org →
T1003.004 LSA Secrets Credential Access
Adversaries with SYSTEM access to a host may attempt to access Local Security Authority (LSA) secrets, which can contain a variety of different credential materials, such as credentials for service accounts.
attack.mitre.org →
T1003.006 DCSync Credential Access
Adversaries may attempt to access credentials and other sensitive information by abusing a Windows Domain Controller's application programming interface (API)(Citation: Microsoft DRSR Dec 2017) (Citation: Microsoft GetNCCChanges) (Citati…
attack.mitre.org →
T1006 Direct Volume Access Stealth
Adversaries may directly access a volume to bypass file access controls and file system monitoring.
attack.mitre.org →
T1007 System Service Discovery Discovery
Adversaries may try to gather information about registered local system services.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-66549Same product: Nextcloud Desktop
CVE-2023-22472Same product: Nextcloud Desktop
CVE-2023-29000Same product: Nextcloud Desktop
CVE-2025-47792Same product: Nextcloud Desktop
CVE-2023-23942Same product: Nextcloud Desktop
CVE-2024-52510Same product: Nextcloud Desktop
CVE-2023-28998Same product: Nextcloud Desktop
CVE-2023-28999Same product: Nextcloud Desktop
CVE-2024-46958Same product: Nextcloud Desktop
CVE-2024-37885Same product: Nextcloud Desktop

Affected Assets

nextcloud
desktop
3.0.0 — 3.6.5

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V6.8.3
  • V11.3.4

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 partial match
blocks

Secure SDLC practices directly prevent nonce/key reuse errors in cryptographic implementations.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.19 Installation of software on operational systems partial match
removes
A.8.24 Use of cryptography partial match
blocks

Mandates proper cryptographic key and nonce management, directly preventing nonce/key-pair reuse.

A.8.26 Application security requirements partial match
removes
A.8.27 Secure system architecture and engineering principles partial match
removes
A.8.28 Secure coding partial match
prevents

Secure-coding rules can require unique nonces, but the control is broader than this single weakness.

A.8.29 Security testing in development and acceptance partial match
finds

Security testing can detect nonce reuse, yet the control addresses many other issues beyond this CWE.

References