Medium severity · published Feb 12, 2020
CVE-2020-7957
The IMAP and LMTP components in Dovecot 2.3.9 before 2.3.9.3 mishandle snippet generation when many characters must be read to compute the snippet and a trailing > character…
5.3
CVSS
1.9%
EPSS
No
On KEV
Description
The IMAP and LMTP components in Dovecot 2.3.9 before 2.3.9.3 mishandle snippet generation when many characters must be read to compute the snippet and a trailing > character exists. This causes a denial of service in which the recipient cannot read all of their messages.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.9% · higher than 79% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DO
Dovecot · Dovecot
2.3.9 before 2.3.9.3 · source: NVD
FE
Fedora · Fedoraproject
30; 31 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-7957
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-7957
Exploit
http://www.openwall.com/lists/oss-security/2020/02/12/2
Exploit
https://dovecot.org/pipermail/dovecot-news/2020-February/000430.html
Vendor Advisory
https://dovecot.org/security
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6XYT55WH372BJOXCJRKBDIFGBMPVOIDT/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NJXHOUT3FH2DJNMACSX4GHPP4MUV4UKA/
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