How severe is CVE-2020-1730?

CVE-2020-1730 has a CVSS 3.x base score of 5.3, rated medium 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 low.

Is CVE-2020-1730 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-1730?

CVE-2020-1730 primarily affects Redhat Enterprise Linux. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-1730?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-1730 published?

CVE-2020-1730 was published on 2020-04-13 and last updated on 2026-06-17.

CVE-2020-1730

CVE-2020-1730 is a medium-severity vulnerability in Redhat Enterprise Linux with a CVSS 3.x base score of 5.3. 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-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Redhat Enterprise Linux
Published: 2020-04-13
Last modified: 2026-06-17

Description

A flaw was found in libssh versions before 0.8.9 and before 0.9.4 in the way it handled AES-CTR (or DES ciphers if enabled) ciphers. The server or client could crash when the connection hasn't been fully initialized and the system tries to cleanup the ciphers when closing the connection. The biggest threat from this vulnerability is system availability.

Frequently asked questions

What is CVE-2020-1730?: A flaw was found in libssh versions before 0.8.9 and before 0.9.4 in the way it handled AES-CTR (or DES ciphers if enabled) ciphers. The server or client could crash when the connection hasn't been fully initialized and the system tries to cleanup the ciphers when closing the connection. The biggest threat from this vulnerability is system availability.
How severe is CVE-2020-1730?: CVE-2020-1730 has a CVSS 3.x base score of 5.3, rated medium 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 low.
Is CVE-2020-1730 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-1730?: CVE-2020-1730 primarily affects Redhat Enterprise Linux. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-1730?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-1730 published?: CVE-2020-1730 was published on 2020-04-13 and last updated on 2026-06-17.

References

Affected products (8)

cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:*
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:mysql_workbench:*:*:*:*:*:*:*:*

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