How severe is CVE-2019-12383?

CVE-2019-12383 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2019-12383 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-12383?

CVE-2019-12383 affects Torproject Tor Browser. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-12383?

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

When was CVE-2019-12383 published?

CVE-2019-12383 was published on 2019-05-28 and last updated on 2026-06-17.

CVE-2019-12383

CVE-2019-12383 is a medium-severity vulnerability in Torproject Tor Browser with a CVSS 3.x base score of 4.3. 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-203.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.3
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Torproject Tor Browser
Published: 2019-05-28
Last modified: 2026-06-17

Description

Tor Browser before 8.0.1 has an information exposure vulnerability. It allows remote attackers to detect the browser's UI locale by measuring a button width, even if the user has a "Don't send my language" setting.

Frequently asked questions

What is CVE-2019-12383?: Tor Browser before 8.0.1 has an information exposure vulnerability. It allows remote attackers to detect the browser's UI locale by measuring a button width, even if the user has a "Don't send my language" setting.
How severe is CVE-2019-12383?: CVE-2019-12383 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2019-12383 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-12383?: CVE-2019-12383 affects Torproject Tor Browser. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-12383?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-12383 published?: CVE-2019-12383 was published on 2019-05-28 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:torproject:tor_browser:*:*:*:*:*:*:*:*

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