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CVE-2020-28020
Exim 4 before 4.92 allows Integer Overflow to Buffer Overflow, in which an unauthenticated remote attacker can execute arbitrary code by…
Critical9.8EPSS 7.9%
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
Exim 4 before 4.92 allows Integer Overflow to Buffer Overflow, in which an unauthenticated remote attacker can execute arbitrary code by leveraging the mishandling of continuation lines during header-length restriction.
Timeline
ID reserved
By mitre
- 6 months later
· 6 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 7.9% · top 5.2% of all CVEs (7 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Weakness
Affected products
n/a
- affected n/a
References (3)
- https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28020-HSIZE.txt (opens in a new tab)x_refsource_MISCx_transferred
- [oss-security] 20210725 CVE-2020-28020: Integer overflow in Exim that can lead to RCE: Some questions to the Qualys researchers who designed the exploit (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [oss-security] 20210802 Re: CVE-2020-28020: Integer overflow in Exim that can lead to RCE: Some questions to the Qualys researchers who designed the exploit (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-28020)Record last updated .