How severe is CVE-2020-28019?

CVE-2020-28019 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-2020-28019 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 61% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-28019?

CVE-2020-28019 affects Exim. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-28019?

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-2020-28019 published?

CVE-2020-28019 was published on 2021-05-06 and last updated on 2026-06-17.

CVE-2020-28019

CVE-2020-28019 is a high-severity vulnerability in Exim with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 61% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-665.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 61% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-665
Affected product: Exim
Published: 2021-05-06
Last modified: 2026-06-17

Description

Exim 4 before 4.94.2 has Improper Initialization that can lead to recursion-based stack consumption or other consequences. This occurs because use of certain getc functions is mishandled when a client uses BDAT instead of DATA.

Frequently asked questions

What is CVE-2020-28019?: Exim 4 before 4.94.2 has Improper Initialization that can lead to recursion-based stack consumption or other consequences. This occurs because use of certain getc functions is mishandled when a client uses BDAT instead of DATA.
How severe is CVE-2020-28019?: CVE-2020-28019 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-2020-28019 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 61% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-28019?: CVE-2020-28019 affects Exim. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-28019?: 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-2020-28019 published?: CVE-2020-28019 was published on 2021-05-06 and last updated on 2026-06-17.

References

https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28019-BDATA.txt

Affected products (1)

cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*

More vulnerabilities in Exim

CVE-2026-45185 — Critical (CVSS 9.8): Exim before 4.99.3, in certain GnuTLS configurations, has a remotely reachable use-after-free in the BDAT body parsing…
CVE-2023-42117 — Critical (CVSS 9.8): Exim Improper Neutralization of Special Elements Remote Code Execution Vulnerability. This vulnerability allows remote…
CVE-2023-42116 — Critical (CVSS 9.8): Exim SMTP Challenge Stack-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote…
CVE-2023-42115 — Critical (CVSS 9.8): Exim AUTH Out-Of-Bounds Write Remote Code Execution Vulnerability. This vulnerability allows remote attackers to…
CVE-2022-37452 — Critical (CVSS 9.8): Exim before 4.95 has a heap-based buffer overflow for the alias list in host_name_lookup in host.c when…
CVE-2020-28026 — Critical (CVSS 9.8): Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in non-default configurations that enable…

All CVEs affecting Exim →

Other CWE-665 (Improper Initialization) vulnerabilities

CVE-2021-33635 — Critical (CVSS 9.8): When malicious images are pulled by isula pull, attackers can execute arbitrary code.
CVE-2022-37128 — Critical (CVSS 9.8): In D-Link DIR-816 A2_v1.10CNB04.img the network can be initialized without authentication via /goform/wizard_end.
CVE-2021-41264 — Critical (CVSS 9.8): OpenZeppelin Contracts is a library for smart contract development. In affected versions upgradeable contracts using…
CVE-2019-10196 — Critical (CVSS 9.8): A flaw was found in http-proxy-agent, prior to version 2.1.0. It was discovered http-proxy-agent passes an auth option…
CVE-2015-8367 — Critical (CVSS 9.8): The phase_one_correct function in Libraw before 0.17.1 allows attackers to cause memory errors and possibly execute…
CVE-2019-14271 — Critical (CVSS 9.8): In Docker 19.03.x before 19.03.1 linked against the GNU C Library (aka glibc), code injection can occur when the…

Browse all CWE-665 (Improper Initialization) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

76.12.128.249 (ipv4-addr)
50.116.72.139 (ipv4-addr)
166.62.41.190 (ipv4-addr)
132.148.155.138 (ipv4-addr)
50.62.22.47 (ipv4-addr)
31.131.22.122 (ipv4-addr)
193.68.57.43 (ipv4-addr)
192.169.201.223 (ipv4-addr)