SB2020022709 - Multiple vulnerabilities in Pure-FTPd
Published: February 27, 2020 Updated: June 21, 2025
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 secuirty vulnerabilities.
1) Out-of-bounds read (CVE-ID: CVE-2020-9365)
The vulnerability allows a remote authenticated user to gain access to potentially sensitive information.The vulnerability exists due to a boundary condition within the pure_strcmp function in utils.c. A remote authenticated user can use a specially crafted FTP command to trigger out-of-bounds read error and read contents of memory on the system.
2) Access of Uninitialized Pointer (CVE-ID: CVE-2020-9274)
The vulnerability allows a remote attacker to perform a denial of service attack.
The vulnerability exists due to access to an uninitialized pointer in init_aliases() function in diraliases.c when processing liked. A remote user with ability to create aliases can crash the server.
3) Resource exhaustion (CVE-ID: CVE-2019-20176)
The vulnerability allows a remote user to perform a denial of service (DoS) attack.
The vulnerability exists due to a stack exhaustion issue in the listdir() function in ls.c. A remote authenticated user can use a specially crafted LS command to perform a denial of service (DoS) attack.
4) Arbitrary file upload (CVE-ID: CVE-2021-40524)
The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.
In Pure-FTPd before 1.0.50, an incorrect max_filesize quota mechanism in the server allows attackers to upload files of unbounded size, which may lead to denial of service or a server hang. This occurs because a certain greater-than-zero test does not anticipate an initial -1 value. (Versions 1.0.23 through 1.0.49 are affected.)
Remediation
Install update from vendor's website.
References
- https://github.com/jedisct1/pure-ftpd/commit/36c6d268cb190282a2c17106acfd31863121b58e
- https://github.com/jedisct1/pure-ftpd/commit/8d0d42542e2cb7a56d645fbe4d0ef436e38bcefa
- https://www.pureftpd.org/project/pure-ftpd/news/
- https://github.com/jedisct1/pure-ftpd/commit/aea56f4bcb9948d456f3fae4d044fd3fa2e19706
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/AHZG5FPCRMCB6Z3L7FPICC6BZ5ZATFTO/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PICL3U2J4EPGBLOE555Y5RAZTQL3WBBV/
- https://github.com/jedisct1/pure-ftpd/commit/37ad222868e52271905b94afea4fc780d83294b4
- https://github.com/jedisct1/pure-ftpd/compare/1.0.49...1.0.50
- https://github.com/jedisct1/pure-ftpd/pull/158