Vulnerabilities > CVE-2020-28025 - Out-of-bounds Read vulnerability in Exim

CVSS 7.5 - HIGH

Attack vector

NETWORK

Attack complexity

LOW

Privileges required

NONE

Confidentiality impact

HIGH

Integrity impact

NONE

Availability impact

NONE

network

low complexity

exim

CWE-125

NVD

Published: 2021-05-06

Updated: 2021-05-10

Summary

Exim 4 before 4.94.2 allows Out-of-bounds Read because pdkim_finish_bodyhash does not validate the relationship between sig->bodyhash.len and b->bh.len; thus, a crafted DKIM-Signature header might lead to a leak of sensitive information from process memory.

Vulnerable Configurations

Part	Description	Count
Application	Exim Exim Exim 4.00 Exim Exim 4.01 Exim Exim 4.02 Exim Exim 4.03 Exim Exim 4.04 Exim Exim 4.05 Exim Exim 4.10 Exim Exim 4.11 Exim Exim 4.12 Exim Exim 4.14 Exim Exim 4.20 Exim Exim 4.21 Exim Exim 4.22 Exim Exim 4.23 Exim Exim 4.24 Exim Exim 4.30 Exim Exim 4.31 Exim Exim 4.32 Exim Exim 4.33 Exim Exim 4.34 Exim Exim 4.40 Exim Exim 4.41 Exim Exim 4.42 Exim Exim 4.43 Exim Exim 4.44 Exim Exim 4.50 Exim Exim 4.51 Exim Exim 4.52 Exim Exim 4.53 Exim Exim 4.54 Exim Exim 4.60 Exim Exim 4.61 Exim Exim 4.62 Exim Exim 4.63 Exim Exim 4.64 Exim Exim 4.65 Exim Exim 4.66 Exim Exim 4.67 Exim Exim 4.68 Exim Exim 4.69 Exim Exim 4.70 Exim Exim 4.71 Exim Exim 4.72 Exim Exim 4.73 Exim Exim 4.74 Exim Exim 4.75 Exim Exim 4.76 Exim Exim 4.77 Exim Exim 4.80 Exim Exim 4.80.1 Exim Exim 4.82 Exim Exim 4.82.1 Exim Exim 4.84.2 Exim Exim 4.85 Exim Exim 4.85.1 Exim Exim 4.85.2 Exim Exim 4.86 Exim Exim 4.86.1 Exim Exim 4.86.2 Exim Exim 4.87 Exim Exim 4.87.1 Exim Exim 4.88 Exim Exim 4.89 Exim Exim 4.89.1 Exim Exim 4.90 Exim Exim 4.90.0.22 Exim Exim 4.90.0.27 Exim Exim 4.90.1 Exim Exim 4.91 Exim Exim 4.92 Exim Exim 4.92.1 Exim Exim 4.92.2 Exim Exim 4.93 Exim Exim 4.93.0.4 Exim Exim 4.93.0.4-3.1 Exim Exim 4.94 Exim Exim 4.94.1	122

Common Weakness Enumeration (CWE)

CWE-125 - Out-of-bounds Read

Common Attack Pattern Enumeration and Classification (CAPEC)

Overread Buffers
An adversary attacks a target by providing input that causes an application to read beyond the boundary of a defined buffer. This typically occurs when a value influencing where to start or stop reading is set to reflect positions outside of the valid memory location of the buffer. This type of attack may result in exposure of sensitive information, a system crash, or arbitrary code execution.

References

https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28025-BHASH.txt