CVE-2026-72522: libexpat_project libexpat Out-of-bounds Read
CVSS: 6.2v3.1MediumDeferred
AliasesRHSA-2026:54869UBUNTU-CVE-2026-72522DEBIAN-CVE-2026-72522
Published 10-08-2026Last modified 13-08-2026
Vulnerability summary
CVE-2026-72522 is a medium (CVSS 6.2) Out-of-bounds Read vulnerability in libexpat_project libexpat. EPSS estimates a 0.19% chance of exploitation in the next 30 days, higher than 8.2% of scored vulnerabilities.
CVSS score
6.2/10
010
Medium · v3.1 (CVE.org)EPSS score
0.19%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 13 · Related 12Timeline
- 10-08-2026PublishedVulnerability first disclosed.
- 13-08-2026Last modifiedVulnerability information updated.
Description
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.
CVSS metrics
5 scores · 5 sources · 1 versionMedium 6.2Preferred score · CVE.org (CNA)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSourcesAll 5 agree
- OSV · Red hatEcosystem advisory · calculated6.2MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated6.2MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated6.2MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVDNIST6.2MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.19%
Chance of exploitation in the next 30 days
Percentile
8%
Versus all other CVEs
30-day change
0.00 pp
From 0.19% on 19-09-2026
19-09-202619-10-2026
EPSS score0.19%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu16 products
- ayttmAll versions (No fix recorded)
- cableswigAll versions (No fix recorded)
- cadaverAll versions (No fix recorded)
- coin3All versions (No fix recorded)
- expat< 2.1.0-4ubuntu1.4+esm13 | < 2.1.0-7ubuntu0.16.04.5+esm14 | < 2.2.5-3ubuntu0.9+esm5 | < 2.2.9-1ubuntu0.8+esm3 | < 2.4.7-1ubuntu0.9 | < 2.6.1-2ubuntu0.6 | < 2.7.4-1ubuntu0.2
Redhat3 products
- expat< 0:2.8.3-0.1.hum1
- expat-devel< 0:2.8.3-0.1.hum1
- expat-static< 0:2.8.3-0.1.hum1
Debian1 product
- expat< 2.5.0-1+deb12u3 | < 2.8.3-1~deb13u1 | < 2.8.3-1
Libexpat_project1 product
- libexpat< 2.8.3
4 vendors · 21 products
References
14 links- images.redhat.comARTICLE
