CVE-2026-72522

EUVD-2026-54990
libexpat before 2.8.3 has an out-of-bounds read and resultant infinite loop because low surrogates are treated the same as high surrogates during Unicode processing in the *_toUtf16 functions.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
mitreCNA
6.2 MEDIUM
LOCAL
LOW
NONE
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 7.02%
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
libexpat_projectlibexpat
𝑥
< 2.8.3
CNA
Debian logo
Debian Releases
Debian Product
Codename
expat
bookworm
vulnerable
bookworm (security)
2.5.0-1+deb12u3
fixed
forky
2.8.4-1
fixed
sid
2.8.4-1
fixed
trixie
2.8.3-1~deb13u1
fixed
trixie (security)
2.8.3-1~deb13u1
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
expat
bionic
Fixed 2.2.5-3ubuntu0.9+esm5
released
focal
Fixed 2.2.9-1ubuntu0.8+esm3
released
jammy
Fixed 2.4.7-1ubuntu0.9
released
noble
Fixed 2.6.1-2ubuntu0.6
released
resolute
Fixed 2.7.4-1ubuntu0.2
released
trusty
Fixed 2.1.0-4ubuntu1.4+esm13
released
xenial
Fixed 2.1.0-7ubuntu0.16.04.5+esm14
released
apache2
bionic
not-affected
focal
not-affected
jammy
not-affected
noble
not-affected
resolute
not-affected
trusty
not-affected
xenial
not-affected
apr-util
bionic
not-affected
focal
not-affected
jammy
not-affected
noble
not-affected
resolute
not-affected
trusty
not-affected
xenial
not-affected
cmake
bionic
not-affected
focal
not-affected
jammy
not-affected
noble
not-affected
resolute
not-affected
xenial
not-affected
ghostscript
bionic
not-affected
focal
not-affected
jammy
not-affected
noble
not-affected
resolute
not-affected
xenial
not-affected
texlive-bin
bionic
not-affected
focal
not-affected
jammy
not-affected
noble
not-affected
resolute
not-affected
xenial
not-affected
xmlrpc-c
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
resolute
needs-triage
trusty
needs-triage
xenial
needs-triage
vnc4
bionic
needs-triage
jammy
dne
noble
dne
resolute
dne
trusty
needs-triage
xenial
needs-triage
wbxml2
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
resolute
needs-triage
xenial
needs-triage
swish-e
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
resolute
needs-triage
xenial
needs-triage
insighttoolkit4
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
dne
resolute
dne
xenial
needs-triage
cadaver
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
resolute
needs-triage
xenial
needs-triage
gdcm
bionic
needs-triage
focal
not-affected
jammy
not-affected
noble
not-affected
resolute
not-affected
trusty
not-affected
xenial
needs-triage
ayttm
jammy
dne
noble
dne
resolute
dne
xenial
needs-triage
cableswig
jammy
dne
noble
dne
resolute
dne
xenial
needs-triage
coin3
bionic
needs-triage
focal
not-affected
jammy
not-affected
noble
not-affected
resolute
not-affected
trusty
needs-triage
xenial
needs-triage
matanza
bionic
needs-triage
focal
ignored
jammy
ignored
noble
ignored
resolute
ignored
xenial
needs-triage
tdom
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
resolute
needs-triage
xenial
needs-triage
vtk
jammy
dne
noble
dne
resolute
dne
trusty
needs-triage
xenial
needs-triage
smart
bionic
needs-triage
jammy
dne
noble
dne
resolute
dne
xenial
needs-triage
firefox
jammy
not-affected
noble
not-affected
resolute
not-affected
thunderbird
jammy
not-affected
noble
not-affected
resolute
not-affected
libxmltok
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
resolute
dne
xenial
needs-triage
Amazon Linux logo
Amazon Linux Releases
Amazon Package
Release
firefox
Amazon Linux 2023
0:140.14.0-1.amzn2023.0.1
fixed
firefox-debuginfo
Amazon Linux 2023
0:140.14.0-1.amzn2023.0.1
fixed
firefox-debugsource
Amazon Linux 2023
0:140.14.0-1.amzn2023.0.1
fixed
thunderbird
Amazon Linux 2
0:140.14.0-1.amzn2.0.1
fixed
Azure Linux logo
Azure Linux Releases
Azure Package
Release
expat
Azure Linux 3.0
0:2.8.3-1.azl3
fixed
Common Weakness Enumeration
References
https://bugzilla.mozilla.org/show_bug.cgi?id=2053153
https://github.com/libexpat/libexpat/pull/1296
http://www.openwall.com/lists/oss-security/2026/08/11/5