How severe is CVE-2017-7842?

CVE-2017-7842 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-2017-7842 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-7842?

CVE-2017-7842 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-7842?

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

When was CVE-2017-7842 published?

CVE-2017-7842 was published on 2018-06-11 and last updated on 2026-06-17.

CVE-2017-7842

CVE-2017-7842 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% (72nd 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

If a document's Referrer Policy attribute is set to "no-referrer" sometimes two network requests are made for "<link>" elements instead of one. One of these requests includes the referrer instead of respecting the set policy to not include a referrer on requests. This vulnerability affects Firefox < 57.

Frequently asked questions

What is CVE-2017-7842?: If a document's Referrer Policy attribute is set to "no-referrer" sometimes two network requests are made for "<link>" elements instead of one. One of these requests includes the referrer instead of respecting the set policy to not include a referrer on requests. This vulnerability affects Firefox < 57.
How severe is CVE-2017-7842?: CVE-2017-7842 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-2017-7842 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-7842?: CVE-2017-7842 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-7842?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-7842 published?: CVE-2017-7842 was published on 2018-06-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

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