CVE-2026-72522: CWE-125 Out-of-bounds Read in libexpat project libexpat
CVE-2026-72522 is an out-of-bounds read vulnerability in libexpat versions before 2.8.3. The issue arises because low surrogate Unicode characters are incorrectly treated the same as high surrogates during Unicode processing in the *_toUtf16 functions. This flaw can cause an infinite loop during processing.
AI Analysis
Technical Summary
The libexpat library prior to version 2.8.3 contains a vulnerability where low surrogate Unicode characters are mishandled as high surrogates in the *_toUtf16 functions. This results in an out-of-bounds read and can lead to an infinite loop condition. The vulnerability is classified under CWE-125 (Out-of-bounds Read).
Potential Impact
This vulnerability does not impact confidentiality or integrity but can cause a denial of service due to an infinite loop (availability impact). The CVSS 3.1 score is 6.2 (medium severity) with the vector indicating local attack vector, low complexity, no privileges required, no user interaction, and impact limited to availability.
Mitigation Recommendations
No official patch or remediation level is currently confirmed. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted input that could trigger the vulnerability.
CVE-2026-72522: CWE-125 Out-of-bounds Read in libexpat project libexpat
Description
CVE-2026-72522 is an out-of-bounds read vulnerability in libexpat versions before 2.8.3. The issue arises because low surrogate Unicode characters are incorrectly treated the same as high surrogates during Unicode processing in the *_toUtf16 functions. This flaw can cause an infinite loop during processing.
CVSS v3.1
Score 6.2medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The libexpat library prior to version 2.8.3 contains a vulnerability where low surrogate Unicode characters are mishandled as high surrogates in the *_toUtf16 functions. This results in an out-of-bounds read and can lead to an infinite loop condition. The vulnerability is classified under CWE-125 (Out-of-bounds Read).
Potential Impact
This vulnerability does not impact confidentiality or integrity but can cause a denial of service due to an infinite loop (availability impact). The CVSS 3.1 score is 6.2 (medium severity) with the vector indicating local attack vector, low complexity, no privileges required, no user interaction, and impact limited to availability.
Mitigation Recommendations
No official patch or remediation level is currently confirmed. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted input that could trigger the vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-08-10T03:28:03.899Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a794bfbbf8831d539ef0fec
Added to database: 08/10/2026, 03:56:43 UTC
Last enriched: 08/10/2026, 04:16:38 UTC
Last updated: 08/10/2026, 06:27:32 UTC
Views: 15
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