How severe is CVE-2015-1777?

CVE-2015-1777 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2015-1777 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-1777?

CVE-2015-1777 affects Redhat Rhn-client-tools. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2015-1777?

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

When was CVE-2015-1777 published?

CVE-2015-1777 was published on 2018-04-12 and last updated on 2026-06-17.

CVE-2015-1777

CVE-2015-1777 is a medium-severity vulnerability in Redhat Rhn-client-tools with a CVSS 3.x base score of 5.9. 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Redhat Rhn-client-tools
Published: 2018-04-12
Last modified: 2026-06-17

Description

rhnreg_ks in Red Hat Network Client Tools (aka rhn-client-tools) on Red Hat Gluster Storage 2.1 and Enterprise Linux (RHEL) 5, 6, and 7 does not properly validate hostnames in X.509 certificates from SSL servers, which allows remote attackers to prevent system registration via a man-in-the-middle attack.

Frequently asked questions

What is CVE-2015-1777?: rhnreg_ks in Red Hat Network Client Tools (aka rhn-client-tools) on Red Hat Gluster Storage 2.1 and Enterprise Linux (RHEL) 5, 6, and 7 does not properly validate hostnames in X.509 certificates from SSL servers, which allows remote attackers to prevent system registration via a man-in-the-middle attack.
How severe is CVE-2015-1777?: CVE-2015-1777 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2015-1777 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-1777?: CVE-2015-1777 affects Redhat Rhn-client-tools. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2015-1777?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-1777 published?: CVE-2015-1777 was published on 2018-04-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:redhat:rhn-client-tools:*:*:*:*:*:*:*:*

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