Fedora EPEL 7 update for libasr, opensmtpd



| Updated: 2025-04-25
Risk Critical
Patch available YES
Number of vulnerabilities 3
CVE-ID CVE-2020-7247
CVE-2020-8794
CVE-2020-8793
CWE-ID CWE-78
CWE-125
CWE-264
Exploitation vector Network
Public exploit Vulnerability #1 is being exploited in the wild.
Public exploit code for vulnerability #2 is available.
Public exploit code for vulnerability #3 is available.
Vulnerable software
 Fedora
Operating systems & Components / Operating system

opensmtpd
Operating systems & Components / Operating system package or component

libasr
Operating systems & Components / Operating system package or component

Vendor Fedoraproject

Security Bulletin

This security bulletin contains information about 3 vulnerabilities.

1) OS Command Injection

EUVDB-ID: #VU24745

Risk: Critical

CVSSv4.0: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red]

CVE-ID: CVE-2020-7247

CWE-ID: CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to execute arbitrary shell commands on the target system.

The vulnerability exists due to improper validation of user-supplied input passed within the smtp_mailaddr() function. A remote unauthenticated attacker can send a specially crafted MAIL FROM command and execute arbitrary OS commands on the target system with root privileges.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Install updates from vendor's repository.

Vulnerable software versions

Fedora: 7

opensmtpd: before 6.6.4p1-3.el7

libasr: before 1.0.4-2.el7

CPE2.3 External links

https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2020-ede50a3d8b


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.

2) Out-of-bounds read

EUVDB-ID: #VU25625

Risk: Medium

CVSSv4.0: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:A/U:Green]

CVE-ID: CVE-2020-8794

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition in mta_io() function in mta_session.c for multi-line replies during mail delivery. A remote attacker can use a mail server to send specially crafted replies, trigger out-of-bounds read error and read contents of memory on the system.

Mitigation

Install updates from vendor's repository.

Vulnerable software versions

Fedora: 7

opensmtpd: before 6.6.4p1-3.el7

libasr: before 1.0.4-2.el7

CPE2.3 External links

https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2020-ede50a3d8b


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, a fully functional exploit for this vulnerability is available.

3) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU25586

Risk: Low

CVSSv4.0: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P/U:Clear]

CVE-ID: CVE-2020-8793

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: Yes

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to the application does not drop privileges when executing the "/usr/sbin/smtpctl" application with  a "-bi" command-line argument. A local user can leverage this behavior and use a specially crafted hardlink to execute arbitrary code on the system with elevated privileges.

Mitigation

Install updates from vendor's repository.

Vulnerable software versions

Fedora: 7

opensmtpd: before 6.6.4p1-3.el7

libasr: before 1.0.4-2.el7

CPE2.3 External links

https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2020-ede50a3d8b


Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.



###SIDEBAR###