Cyber Resilience

CVE-2023-23944

Nextcloud Mail ≤ 2.2.2

Published
06 February 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 2.0
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:N/A:N
EPSS Score 0.0047 39th percentile
Risk Priority 22 floored blend · peak EPSS

Summary

CVE-2023-23944 is a low-severity Cleartext Storage of Sensitive Information (CWE-312) vulnerability in Nextcloud Mail. Its CVSS base score is 2.0 (Low).

Operationally, exploitation aligns with the MITRE ATT&CK technique Credentials In Files (T1552.001); ranked at the 39th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Nextcloud mail is an email app for the nextcloud home server platform. In versions prior to 2.2.2 user's passwords were stored in cleartext in the database during the duration of OAuth2 setup procedure. Any attacker or malicious user with access…

more

to the database would have access to these user passwords until the OAuth setup has been completed. It is recommended that the Nextcloud Mail app is upgraded to 2.2.2. There are no known workarounds for this issue.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1552.001 Credentials In Files Credential Access
Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials.
T1552.004 Private Keys Credential Access
Adversaries may search for private key certificate files on compromised systems for insecurely stored credentials.
T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
T1552.002 Credentials in Registry Credential Access
Adversaries may search the Registry on compromised systems for insecurely stored credentials.
T1552.006 Group Policy Preferences Credential Access
Adversaries may attempt to find unsecured credentials in Group Policy Preferences (GPP).
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-52508Same product: Nextcloud Mail
CVE-2024-52509Same product: Nextcloud Mail
CVE-2023-25160Same product: Nextcloud Mail
CVE-2023-33184Same product: Nextcloud Mail
CVE-2023-48305Same vendor: Nextcloud
CVE-2023-48307Same product: Nextcloud Mail
CVE-2025-66514Same product: Nextcloud Mail
CVE-2023-23943Same product: Nextcloud Mail
CVE-2023-45151Same vendor: Nextcloud
CVE-2023-45660Same product: Nextcloud Mail

Affected Assets

nextcloud
mail
≤ 2.2.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 4 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V14.2.8

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-312

Training on secure data handling discourages cleartext storage of sensitive information.

addresses: CWE-312

Data action mapping can detect storage actions that leave sensitive information in cleartext.

addresses: CWE-312

Configuration policies can mandate secure storage methods to avoid cleartext storage of sensitive information.

addresses: CWE-312

Policy requires protection measures such as encryption for sensitive data stored on media, preventing cleartext exposure.

addresses: CWE-312

Key-management policy requires protected storage of key material, preventing cleartext storage of sensitive cryptographic keys.

addresses: CWE-312

Requiring confidentiality protection for information at rest eliminates cleartext storage of sensitive data on persistent media.

addresses: CWE-312

Reduces cleartext storage of sensitive data when OPSEC identifies and mandates protection of key information artifacts.

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.DS-01 full match
prevents

Encryption and cryptographic controls for data-at-rest directly prevent cleartext storage of sensitive information.

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.

mitigates

Requiring non-standard deletion or physical destruction of media ensures that sensitive information is not left in cleartext on discarded or repurposed equipment.

mitigates

Secure deletion of data before device transfer prevents residual sensitive information from remaining in cleartext on storage media that leave organizational control.

mitigates

Secure deletion of obsolete or temporary copies prevents sensitive data from remaining in cleartext on disk after its intended lifetime.

A.8.11 Data masking partial match
mitigates

Substituting real values with hashes or encrypted tokens before storage reduces the quantity of cleartext sensitive information that ends up persisted on disk.

finds

When clear-text sensitive data is detected leaving controlled storage, the control can block the transfer, thereby limiting the exposure that would result from unencrypted storage on external media or cloud services.

mitigates

By insisting that any retained test copies be stored securely and only for testing, the control reduces the likelihood that clear-text operational data will persist on disk or in backups.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248525 All OL 8 local disk partitions must implement cryptographic mechanisms to prevent unauthorized disclosure or modification of all information that requires at-rest protection. prevents CWE-312
Oracle Linux 9 (1 rule)
  • V-271756 OL 9 local disk partitions must implement cryptographic mechanisms to prevent unauthorized disclosure or modification of all information that requires at rest protection. prevents CWE-312
RHEL 8 (1 rule)
  • V-230224 All RHEL 8 local disk partitions must implement cryptographic mechanisms to prevent unauthorized disclosure or modification of all information that requires at rest protection. prevents CWE-312

References