How severe is CVE-2023-25728?

CVE-2023-25728 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2023-25728 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-25728?

CVE-2023-25728 primarily affects Mozilla Firefox. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-25728?

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

When was CVE-2023-25728 published?

CVE-2023-25728 was published on 2023-06-02 and last updated on 2026-06-17.

CVE-2023-25728

CVE-2023-25728 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 6.5. 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-203.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Mozilla Firefox
Published: 2023-06-02
Last modified: 2026-06-17

Description

The <code>Content-Security-Policy-Report-Only</code> header could allow an attacker to leak a child iframe's unredacted URI when interaction with that iframe triggers a redirect. This vulnerability affects Firefox < 110, Thunderbird < 102.8, and Firefox ESR < 102.8.

Frequently asked questions

What is CVE-2023-25728?: The <code>Content-Security-Policy-Report-Only</code> header could allow an attacker to leak a child iframe's unredacted URI when interaction with that iframe triggers a redirect. This vulnerability affects Firefox < 110, Thunderbird < 102.8, and Firefox ESR < 102.8.
How severe is CVE-2023-25728?: CVE-2023-25728 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2023-25728 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-25728?: CVE-2023-25728 primarily affects Mozilla Firefox. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-25728?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-25728 published?: CVE-2023-25728 was published on 2023-06-02 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

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