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Fencer Vulns
high 7.1

CVE-2017-13720 json

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 connecti…

published 2017-10-11 9 y ago modified 2026-06-17 4 mo ago also EUVD-2017-5237

cvss
7.1
version 3.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 38%
public exploits
0
none known

Summary

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.

Patch / fix

  • libxfont Debian 14, Debian 13, Debian 12 1:2.0.1-4

debian advisories DEBIAN-CVE-2017-13720

  • libxfont Ubuntu 14.04 LTS 1:1.4.7-1ubuntu0.3
  • libxfont Ubuntu 16.04 LTS 1:1.5.1-1ubuntu0.16.04.3
  • libxfont2 Ubuntu 16.04 LTS 1:2.0.1-3~ubuntu16.04.2

ubuntu advisories UBUNTU-CVE-2017-13720

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • libXfont SLES for SAP 12 SP3, SLES for SAP 12 SP2, SLES for Raspberry Pi 12 SP2 +6 more 1.5.1-11.3.12
  • xorg-x11-libs SLES for SAP 11 SP4, SLES 11 SP4, SLE Software Development Kit 11 SP4 7.4-8.26.50.5.3

suse advisories SUSE-SU-2018:0334-1SUSE-SU-2018:0246-1

  • libXfont openSUSE Tumbleweed 1.5.4-2.18

opensuse advisories openSUSE-SU-2024:10921-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2017-13720 updated cvss 4.4

libXfont: Insufficient input validation in fontdir.c

  • Red Hat Enterprise Linux 5 libXfont Red Hat Enterprise Linux 6 libXfont Red Hat Enterprise Linux 7 libXfont, libXfont2
    affected: no fix planned “Will not fix”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.44% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.0 7.1 CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
NVD 2.0 3.6 AV:L/AC:L/Au:N/C:P/I:N/A:P

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.