How severe is CVE-2020-1946?

CVE-2020-1946 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-1946 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-1946?

CVE-2020-1946 primarily affects Apache Spamassassin. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-1946?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2020-1946 published?

CVE-2020-1946 was published on 2021-03-25 and last updated on 2026-06-17.

CVE-2020-1946

CVE-2020-1946 is a critical-severity vulnerability in Apache Spamassassin with a CVSS 3.x base score of 9.8. 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-78.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 6% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Apache Spamassassin
Published: 2021-03-25
Last modified: 2026-06-17

Description

In Apache SpamAssassin before 3.4.5, malicious rule configuration (.cf) files can be configured to run system commands without any output or errors. With this, exploits can be injected in a number of scenarios. In addition to upgrading to SA version 3.4.5, users should only use update channels or 3rd party .cf files from trusted places.

Frequently asked questions

What is CVE-2020-1946?: In Apache SpamAssassin before 3.4.5, malicious rule configuration (.cf) files can be configured to run system commands without any output or errors. With this, exploits can be injected in a number of scenarios. In addition to upgrading to SA version 3.4.5, users should only use update channels or 3rd party .cf files from trusted places.
How severe is CVE-2020-1946?: CVE-2020-1946 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-1946 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-1946?: CVE-2020-1946 primarily affects Apache Spamassassin. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-1946?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-1946 published?: CVE-2020-1946 was published on 2021-03-25 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:apache:spamassassin:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

More vulnerabilities in Apache Spamassassin

CVE-2018-11780 — Critical (CVSS 9.8): A potential Remote Code Execution bug exists with the PDFInfo plugin in Apache SpamAssassin before 3.4.2.
CVE-2020-1931 — High (CVSS 8.1): A command execution issue was found in Apache SpamAssassin prior to 3.4.3. Carefully crafted nefarious Configuration…
CVE-2020-1930 — High (CVSS 8.1): A command execution issue was found in Apache SpamAssassin prior to 3.4.3. Carefully crafted nefarious rule…
CVE-2018-11781 — High (CVSS 7.8): Apache SpamAssassin 3.4.2 fixes a local user code injection in the meta rule syntax.
CVE-2016-1238 — High (CVSS 7.8): (1) cpan/Archive-Tar/bin/ptar, (2) cpan/Archive-Tar/bin/ptardiff, (3) cpan/Archive-Tar/bin/ptargrep, (4)…
CVE-2019-12420 — High (CVSS 7.5): In Apache SpamAssassin before 3.4.3, a message can be crafted in a way to use excessive resources. Upgrading to SA…

All CVEs affecting Apache Spamassassin →

Other CWE-78 (OS Command Injection) vulnerabilities

CVE-2026-19188 — Critical (CVSS 10.0): A critical OS command injection vulnerability has been identified in the Haiwell IoT Cloud HMI Gateway product. The…
CVE-2026-48362 — Critical (CVSS 10.0): ColdFusion is affected by an Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')…
CVE-2026-16812 — Critical (CVSS 10.0): VeloCloud Orchestrator (VCO) on-prem has a security issue where this issue may allow a remote attacker to access…
CVE-2026-6516 — Critical (CVSS 10.0): Zohocorp ManageEngine ADAudit Plus versions before 8606 are affected by Unauthenticated Remote code execution due to…
CVE-2026-46339 — Critical (CVSS 10.0): 9Router is an AI router & token saver. From 0.4.30 until 0.4.37, 9Router's src/proxy.js middleware did not protect…
CVE-2026-59726 — Critical (CVSS 10.0): Ruflo is an agent meta-harness for Claude Code and Codex. Prior to 3.16.3, ruflo's default docker-compose deployment…

Browse all CWE-78 (OS Command Injection) vulnerabilities →