Libexpat up to 2.8.2 Unicode *_toUtf16 out-of-bounds

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k3.41

Summaryinfo

A vulnerability identified as critical has been detected in Libexpat up to 2.8.2. This vulnerability affects the function *_toUtf16 of the component Unicode Handler. Performing a manipulation results in out-of-bounds. This vulnerability is identified as CVE-2026-72522. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability, which was classified as critical, was found in Libexpat up to 2.8.2. This affects the function *_toUtf16 of the component Unicode Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-72522 since 08/10/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 2.8.3 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-54990). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Libexpat 2.8.3

Timelineinfo

08/10/2026 Advisory disclosed
08/10/2026 +0 days CVE reserved
08/10/2026 +0 days VulDB entry created
08/10/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-72522 (🔒)
GCVE (CVE): GCVE-0-2026-72522
GCVE (VulDB): GCVE-100-387291
EUVD: 🔒

Entryinfo

Created: 08/10/2026 06:02
Updated: 08/10/2026 07:54
Changes: 08/10/2026 06:02 (55), 08/10/2026 07:54 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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