CVE-2020-28924
CVE-2020-28924 is a high-severity vulnerability in Rclone with a CVSS 3.x base score of 7.5. 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-331.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (68th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-331
- Affected product: Rclone
- Published:
- Last modified:
Description
An issue was discovered in Rclone before 1.53.3. Due to the use of a weak random number generator, the password generator has been producing weak passwords with much less entropy than advertised. The suggested passwords depend deterministically on the time the second rclone was started. This limits the entropy of the passwords enormously. These passwords are often used in the crypt backend for encryption of data. It would be possible to make a dictionary of all possible passwords with about 38 million entries per password length. This would make decryption of secret material possible with a plausible amount of effort. NOTE: all passwords generated by affected versions should be changed.
Frequently asked questions
- What is CVE-2020-28924?
- An issue was discovered in Rclone before 1.53.3. Due to the use of a weak random number generator, the password generator has been producing weak passwords with much less entropy than advertised. The suggested passwords depend deterministically on the time the second rclone was started. This limits the entropy of the passwords enormously. These passwords are often used in the crypt backend for encryption of data. It would be possible to make a dictionary of all possible passwords with about 38 million entries per password length. This would make decryption of secret material possible with a plausible amount of effort. NOTE: all passwords generated by affected versions should be changed.
- How severe is CVE-2020-28924?
- CVE-2020-28924 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2020-28924 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-28924?
- CVE-2020-28924 primarily affects Rclone. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-28924?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2020-28924 published?
- CVE-2020-28924 was published on 2020-11-19 and last updated on 2026-06-17.
References
- https://github.com/rclone/rclone/issues/4783
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UJIFT24Q6EFXLQZ24AER2QGFFZLMIPCD/
- https://rclone.org/downloads/
- https://security.gentoo.org/glsa/202107-14
Affected products (2)
- cpe:2.3:a:rclone:rclone:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
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