CVE-2023-28835 Insecure randomness for default password in nextcloud

2023-03-3018:57:00

CWE-338

GitHub_M

www.cve.org

cve-2023-28835

insecure randomness

nextcloud

password policy

upgrade

CVSS3

3.5

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

REQUIRED

Scope

UNCHANGED

Confidentiality Impact

LOW

Integrity Impact

NONE

Availability Impact

NONE

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N

AI Score

7.9

Confidence

High

EPSS

0.002

Percentile

52.3%

JSON

Nextcloud server is an open source home cloud implementation. In affected versions the generated fallback password when creating a share was using a weak complexity random number generator, so when the sharer did not change it the password could be guessable to an attacker willing to brute force it. It is recommended that the Nextcloud Server is upgraded to 24.0.10 or 25.0.4. This issue only affects users who do not have a password policy enabled, so enabling a password policy is an effective mitigation for users unable to upgrade.

CNA Affected

[
  {
    "vendor": "nextcloud",
    "product": "security-advisories",
    "versions": [
      {
        "version": "< 24.0.10",
        "status": "affected"
      },
      {
        "version": ">= 25.0.0, < 25.0.4",
        "status": "affected"
      }
    ]
  }
]