How severe is CVE-2018-12270?

CVE-2018-12270 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2018-12270 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-12270?

CVE-2018-12270 affects Valvesoftware Steam Client. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-12270?

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

When was CVE-2018-12270 published?

CVE-2018-12270 was published on 2019-05-20 and last updated on 2026-06-17.

CVE-2018-12270

CVE-2018-12270 is a medium-severity vulnerability in Valvesoftware Steam Client with a CVSS 3.x base score of 5.4. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v2: 5.8
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Valvesoftware Steam Client
Published: 2019-05-20
Last modified: 2026-06-17

Description

In Valve Steam 1528829181 BETA, it is possible to perform a homograph / homoglyph attack to create fake URLs in the client, which may trick users into visiting unintended web sites.

Frequently asked questions

What is CVE-2018-12270?: In Valve Steam 1528829181 BETA, it is possible to perform a homograph / homoglyph attack to create fake URLs in the client, which may trick users into visiting unintended web sites.
How severe is CVE-2018-12270?: CVE-2018-12270 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2018-12270 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-12270?: CVE-2018-12270 affects Valvesoftware Steam Client. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-12270?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-12270 published?: CVE-2018-12270 was published on 2019-05-20 and last updated on 2026-06-17.

References

https://github.com/VixusFoxy/CVE/wiki/CVE-2018-12270

Affected products (1)

cpe:2.3:a:valvesoftware:steam_client:1528829181:beta:*:*:*:*:*:*

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