Multiple vulnerabilities in Dovecot IMAP server
| Risk | Medium |
| Patch available | YES |
| Number of vulnerabilities | 3 |
| CVE-ID | CVE-2020-10957 CVE-2020-10958 CVE-2020-10967 |
| CWE-ID | CWE-476 CWE-416 CWE-20 |
| Exploitation vector | Network |
| Public exploit |
Public exploit code for vulnerability #1 is available. Public exploit code for vulnerability #3 is available. |
| Vulnerable software Subscribe |
Dovecot Server applications / Mail servers |
| Vendor | Dovecot |
Security Bulletin
This security bulletin contains information about 3 vulnerabilities.
1) NULL pointer dereference
EUVDB-ID: #VU27981
Risk: Medium
CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2020-10957
CWE-ID:
CWE-476 - NULL Pointer Dereference
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient validation of user-supplied input when processing NOOP command. A remote attacker can send a specially crafted NOOP command to submission, submission-login or lmtp service, trigger a NULL pointer dereference and perform a denial of service attack.
PoC command:
``NOOP EE"FY``Mitigation
Install updates from vendor's website.
Vulnerable software versionsDovecot: 2.3.0 - 2.3.10
External linkshttp://dovecot.org/pipermail/dovecot-news/2020-May/000438.html
http://seclists.org/oss-sec/2020/q2/122
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
How the attacker can exploit this vulnerability?
The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
2) Use-after-free
EUVDB-ID: #VU27983
Risk: Medium
CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2020-10958
CWE-ID:
CWE-416 - Use After Free
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a use-after-free error when processing newline characters. A remote attacker can a specially crafted command to submission, submission-login or lmtp service and perform a denial of service (DoS) attack.
MitigationInstall updates from vendor's website.
Vulnerable software versionsDovecot: 2.3.0 - 2.3.10
External linkshttp://seclists.org/oss-sec/2020/q2/122
http://dovecot.org/pipermail/dovecot-news/2020-May/000438.html
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
How the attacker can exploit this vulnerability?
The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
3) Input validation error
EUVDB-ID: #VU27984
Risk: Medium
CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2020-10967
CWE-ID:
CWE-20 - Improper input validation
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient validation of user-supplied input passed via email message. A remote attacker can send a specially crafted email with empty quoted localpart and crash the submission or lmtp service.
PoC:
Send mail with envelope sender or recipient as ``<""@example.org>``.Mitigation
Install updates from vendor's website.
Vulnerable software versionsDovecot: 2.3.0 - 2.3.10
External linkshttp://seclists.org/oss-sec/2020/q2/122
http://dovecot.org/pipermail/dovecot-news/2020-May/000438.html
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
How the attacker can exploit this vulnerability?
The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
