Medium severity · published Jun 28, 2021
CVE-2020-28200
The Sieve engine in Dovecot before 2.3.15 allows Uncontrolled Resource Consumption, as demonstrated by a situation with a complex regular expression for the regex extension
4.3
CVSS
2%
EPSS
No
On KEV
Description
The Sieve engine in Dovecot before 2.3.15 allows Uncontrolled Resource Consumption, as demonstrated by a situation with a complex regular expression for the regex extension.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.0% · higher than 80% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DO
Dovecot · Dovecot
before 2.3.15 · source: NVD
FE
Fedora · Fedoraproject
33; 34 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-28200
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-28200
Vendor Advisory
https://dovecot.org/security
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JB2VTJ3G2ILYWH5Y2FTY2PUHT2MD6VMI/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TK424DWFO2TKJYXZ2H3XL633TYJL4GQN/
Mailing List
https://www.openwall.com/lists/oss-security/2021/06/28/3
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