DEBIAN-CVE-2026-93990

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Source
https://security-tracker.debian.org/tracker/CVE-2026-93990
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-93990.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-93990
Upstream
Published
2026-09-19T23:17:10Z
Modified
2026-10-01T00:00:08Z
Severity
  • 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X CVSS Calculator
Summary
[none]
Details

Expat before 2.8.5 fails to validate that a high surrogate in UTF-16 input is followed by a low surrogate, allowing malformed UTF-16 sequences to be accepted. Attackers can supply UTF-16 encoded XML containing lone high surrogates that consume the following code unit, causing Expat to pass unpaired surrogates to applications built with XML_UNICODE and to silently replace input characters in other builds.

References

Affected packages

Debian:12 / expat

Package

Name
expat
Purl
pkg:deb/debian/expat?arch=source&distro=bookworm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
2.5.0-1+deb12u4

Affected versions

2.*
2.5.0-1
2.5.0-1+deb12u1
2.5.0-1+deb12u2
2.5.0-1+deb12u3

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-93990.json"

Debian:13 / expat

Package

Name
expat
Purl
pkg:deb/debian/expat?arch=source&distro=trixie

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.7.1-2
2.7.2-1
2.7.3-1
2.7.3-2
2.7.4-1
2.7.5-1
2.8.0-1
2.8.0-2
2.8.1-1
2.8.2-1~deb13u1
2.8.2-1
2.8.3-1~deb13u1
2.8.3-1
2.8.4-1
2.8.4-2
2.8.5-1
2.8.5-2

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-93990.json"

Debian:14 / expat

Package

Name
expat
Purl
pkg:deb/debian/expat?arch=source&distro=forky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
2.8.4-2

Affected versions

2.*
2.7.1-2
2.7.2-1
2.7.3-1
2.7.3-2
2.7.4-1
2.7.5-1
2.8.0-1
2.8.0-2
2.8.1-1
2.8.2-1~deb13u1
2.8.2-1
2.8.3-1~deb13u1
2.8.3-1
2.8.4-1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-93990.json"