CVE-2025-66382: CWE-407 Inefficient Algorithmic Complexity in libexpat project libexpat
In libexpat through 2.7.3, a crafted file with an approximate size of 2 MiB can lead to dozens of seconds of processing time.
AI Analysis
Technical Summary
This vulnerability in libexpat (up to version 2.7.3) is classified as CWE-407 (inefficient algorithmic complexity). It allows an attacker to supply a crafted XML file approximately 2 MiB in size that triggers excessive processing time, potentially causing a denial of service by making the parser consume excessive CPU resources. The CVSS 3.1 base score is 2.9, reflecting low impact with local attack vector, high attack complexity, no privileges required, no user interaction, and only availability impact at a low level. No patch or fix information is provided in the available data.
Potential Impact
The impact is limited to availability degradation due to inefficient processing of a crafted input file. There is no impact on confidentiality or integrity. The vulnerability requires local access to supply the crafted file and has high attack complexity, reducing the likelihood of exploitation. No known exploits exist in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted or suspiciously large XML files with libexpat versions through 2.7.3 to reduce risk of denial of service.
CVE-2025-66382: CWE-407 Inefficient Algorithmic Complexity in libexpat project libexpat
Description
In libexpat through 2.7.3, a crafted file with an approximate size of 2 MiB can lead to dozens of seconds of processing time.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in libexpat (up to version 2.7.3) is classified as CWE-407 (inefficient algorithmic complexity). It allows an attacker to supply a crafted XML file approximately 2 MiB in size that triggers excessive processing time, potentially causing a denial of service by making the parser consume excessive CPU resources. The CVSS 3.1 base score is 2.9, reflecting low impact with local attack vector, high attack complexity, no privileges required, no user interaction, and only availability impact at a low level. No patch or fix information is provided in the available data.
Potential Impact
The impact is limited to availability degradation due to inefficient processing of a crafted input file. There is no impact on confidentiality or integrity. The vulnerability requires local access to supply the crafted file and has high attack complexity, reducing the likelihood of exploitation. No known exploits exist in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted or suspiciously large XML files with libexpat versions through 2.7.3 to reduce risk of denial of service.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2025-11-28T00:00:00.000Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69293eaf842b163e001fac42
Added to database: 11/28/2025, 6:18:23 AM
Last enriched: 4/10/2026, 5:26:16 AM
Last updated: 5/10/2026, 4:14:59 AM
Views: 331
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