Integer overflow in Exim

CVE-2020-28017

Exim 4 before 4.94.2 allows Integer Overflow to Buffer Overflow in receive_add_recipient via an e-mail message with fifty million recipients. NOTE: remote exploitation may be difficult because of resource consumption.

Vulnerability class: Integer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.369 (98.5th percentile), scored .

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 98th percentile — 98.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2020-28017: held from 0.369 to 0.369.

EPSS over last 30 days · oldest: 0.369 · newest: 0.369 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-28017?
CVE-2020-28017 is a critical-severity vulnerability in Exim, classified under Integer Overflow or Wraparound. CVSS score: 9.8/10. Published 2021-05-06.
How severe is CVE-2020-28017?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2020-28017 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.