How severe is CVE-2018-7753?

CVE-2018-7753 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-7753 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-7753?

CVE-2018-7753 primarily affects Mozilla Bleach. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-7753?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2018-7753 published?

CVE-2018-7753 was published on 2018-03-07 and last updated on 2026-06-17.

CVE-2018-7753

CVE-2018-7753 is a critical-severity vulnerability in Mozilla Bleach with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mozilla Bleach
Published: 2018-03-07
Last modified: 2026-06-17

Description

An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.

Frequently asked questions

What is CVE-2018-7753?: An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.
How severe is CVE-2018-7753?: CVE-2018-7753 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-7753 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-7753?: CVE-2018-7753 primarily affects Mozilla Bleach. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-7753?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-7753 published?: CVE-2018-7753 was published on 2018-03-07 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:mozilla:bleach:2.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:bleach:2.1.1:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:bleach:2.1.2:*:*:*:*:*:*:*

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