How severe is CVE-2017-13720?

CVE-2017-13720 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2017-13720 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-13720?

CVE-2017-13720 primarily affects X.org Libxfont. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-13720?

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

When was CVE-2017-13720 published?

CVE-2017-13720 was published on 2017-10-11 and last updated on 2026-06-17.

CVE-2017-13720

CVE-2017-13720 is a high-severity vulnerability in X.org Libxfont with a CVSS 3.x base score of 7.1. 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-125.

Key facts

Severity: High (CVSS 3.x base score 7.1)
CVSS v2: 3.6
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: X.org Libxfont
Published: 2017-10-11
Last modified: 2026-06-17

Description

In the PatternMatch function in fontfile/fontdir.c in libXfont through 1.5.2 and 2.x before 2.0.2, an attacker with access to an X connection can cause a buffer over-read during pattern matching of fonts, leading to information disclosure or a crash (denial of service). This occurs because '\0' characters are incorrectly skipped in situations involving ? characters.

Frequently asked questions

What is CVE-2017-13720?: In the PatternMatch function in fontfile/fontdir.c in libXfont through 1.5.2 and 2.x before 2.0.2, an attacker with access to an X connection can cause a buffer over-read during pattern matching of fonts, leading to information disclosure or a crash (denial of service). This occurs because '\0' characters are incorrectly skipped in situations involving ? characters.
How severe is CVE-2017-13720?: CVE-2017-13720 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2017-13720 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-13720?: CVE-2017-13720 primarily affects X.org Libxfont. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-13720?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2017-13720 published?: CVE-2017-13720 was published on 2017-10-11 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:x.org:libxfont:*:*:*:*:*:*:*:*
cpe:2.3:a:x.org:libxfont:2.0.0:*:*:*:*:*:*:*
cpe:2.3:a:x.org:libxfont:2.0.1:*:*:*:*:*:*:*

More vulnerabilities in X.org Libxfont

CVE-2007-1351 — High (CVSS 8.5): Integer overflow in the bdfReadCharacters function in bdfread.c in (1) X.Org libXfont before 20070403 and (2) freetype…
CVE-2017-13722 — High (CVSS 7.1): In the pcfGetProperties function in bitmap/pcfread.c in libXfont through 1.5.2 and 2.x before 2.0.2, a missing boundary…
CVE-2007-1352 — Low (CVSS 3.8): Integer overflow in the FontFileInitTable function in X.Org libXfont before 20070403 allows remote authenticated users…

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