How severe is CVE-2018-5118?

CVE-2018-5118 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 low, integrity none, and availability none.

Is CVE-2018-5118 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-5118?

CVE-2018-5118 primarily affects Mozilla Firefox. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-5118?

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

When was CVE-2018-5118 published?

CVE-2018-5118 was published on 2018-06-11 and last updated on 2026-06-17.

CVE-2018-5118

CVE-2018-5118 is a medium-severity vulnerability in Mozilla Firefox 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-200.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Mozilla Firefox
Published: 2018-06-11
Last modified: 2026-06-17

Description

The screenshot images displayed in the Activity Stream page displayed when a new tab is opened is created from the meta tags of websites. An issue was discovered where the page could attempt to create these images through "file:" URLs from the local file system. This loading is blocked by the sandbox but could expose local data if combined with another attack that escapes sandbox protections. This vulnerability affects Firefox < 58.

Frequently asked questions

What is CVE-2018-5118?: The screenshot images displayed in the Activity Stream page displayed when a new tab is opened is created from the meta tags of websites. An issue was discovered where the page could attempt to create these images through "file:" URLs from the local file system. This loading is blocked by the sandbox but could expose local data if combined with another attack that escapes sandbox protections. This vulnerability affects Firefox < 58.
How severe is CVE-2018-5118?: CVE-2018-5118 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 low, integrity none, and availability none.
Is CVE-2018-5118 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-5118?: CVE-2018-5118 primarily affects Mozilla Firefox. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-5118?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-5118 published?: CVE-2018-5118 was published on 2018-06-11 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:17.10:*:*:*:*:*:*:*

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