CVE-2020-10957
CVE-2020-10957 is a high-severity vulnerability in Dovecot with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 7% (94th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-476
- Affected product: Dovecot
- Published:
- Last modified:
Description
In Dovecot before 2.3.10.1, unauthenticated sending of malformed parameters to a NOOP command causes a NULL Pointer Dereference and crash in submission-login, submission, or lmtp.
Frequently asked questions
- What is CVE-2020-10957?
- In Dovecot before 2.3.10.1, unauthenticated sending of malformed parameters to a NOOP command causes a NULL Pointer Dereference and crash in submission-login, submission, or lmtp.
- How severe is CVE-2020-10957?
- CVE-2020-10957 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2020-10957 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-10957?
- CVE-2020-10957 affects Dovecot. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-10957?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2020-10957 published?
- CVE-2020-10957 was published on 2020-05-18 and last updated on 2026-06-17.
References
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00059.html
- http://packetstormsecurity.com/files/157771/Open-Xchange-Dovecot-2.3.10-Null-Pointer-Dereference-Denial-Of-Service.html
- http://seclists.org/fulldisclosure/2020/May/37
- http://www.openwall.com/lists/oss-security/2020/05/18/1
- https://dovecot.org/security
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TTZN2VW55ZC2AQBGBJMLRJSZIKSB2NS6/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VVUWHUUAFPC6XGIXYFIPTNBXLHPNM4W6/
- https://usn.ubuntu.com/4361-1/
- https://www.debian.org/security/2020/dsa-4690
- https://www.openwall.com/lists/oss-security/2020/05/18/1
Affected products (1)
- cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:*
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