How severe is CVE-2018-12911?

CVE-2018-12911 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-2018-12911 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-12911?

CVE-2018-12911 primarily affects Webkitgtk Webkitgtk+. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-12911?

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-2018-12911 published?

CVE-2018-12911 was published on 2018-07-19 and last updated on 2026-06-17.

CVE-2018-12911

CVE-2018-12911 is a critical-severity vulnerability in Webkitgtk Webkitgtk+ 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-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Webkitgtk Webkitgtk+
Published: 2018-07-19
Last modified: 2026-06-17

Description

WebKitGTK+ 2.20.3 has an off-by-one error, with a resultant out-of-bounds write, in the get_simple_globs functions in ThirdParty/xdgmime/src/xdgmimecache.c and ThirdParty/xdgmime/src/xdgmimeglob.c.

Frequently asked questions

What is CVE-2018-12911?: WebKitGTK+ 2.20.3 has an off-by-one error, with a resultant out-of-bounds write, in the get_simple_globs functions in ThirdParty/xdgmime/src/xdgmimecache.c and ThirdParty/xdgmime/src/xdgmimeglob.c.
How severe is CVE-2018-12911?: CVE-2018-12911 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-2018-12911 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-12911?: CVE-2018-12911 primarily affects Webkitgtk Webkitgtk+. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-12911?: 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-2018-12911 published?: CVE-2018-12911 was published on 2018-07-19 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:webkitgtk:webkitgtk\+:2.20.3:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*

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