libexpat up to 2.7.3 File algorithmic complexity

CVSS Meta Temp Score
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CTI Interest Score
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3.6$0-$5k0.00

Summaryinfo

A vulnerability was found in libexpat up to 2.7.3. It has been declared as problematic. This impacts an unknown function of the component File Handler. The manipulation results in algorithmic complexity. This vulnerability was named CVE-2025-66382. The attack needs to be approached locally. There is no available exploit.

Detailsinfo

A vulnerability classified as problematic has been found in libexpat up to 2.7.3. Affected is some unknown processing of the component File Handler. The manipulation with an unknown input leads to a algorithmic complexity vulnerability. CWE is classifying the issue as CWE-407. An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached. This is going to have an impact on availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is traded as CVE-2025-66382 since 11/28/2025. The exploitability is told to be difficult. Local access is required to approach this attack. The technical details are unknown and an exploit is not available.

The vulnerability scanner Nessus provides a plugin with the ID 276983 (Linux Distros Unpatched Vulnerability : CVE-2025-66382), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (276983), EUVD (EUVD-2025-199862) and CERT Bund (WID-SEC-2025-2696). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Open Source expat

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.6
VulDB Meta Temp Score: 3.6

VulDB Base Score: 2.5
VulDB Temp Score: 2.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CNA Base Score: 2.9
CNA Vector (MITRE): 🔒

CVSSv2info

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

Exploitinginfo

Class: Algorithmic complexity
CWE: CWE-407 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 276983
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-66382

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/28/2025 Advisory disclosed
11/28/2025 +0 days CVE reserved
11/28/2025 +0 days VulDB entry created
12/19/2025 +21 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2025-66382 (🔒)
GCVE (CVE): GCVE-0-2025-66382
GCVE (VulDB): GCVE-100-333738
EUVD: 🔒
CERT Bund: WID-SEC-2025-2696 - expat: Schwachstelle ermöglicht Denial of Service

Entryinfo

Created: 11/28/2025 07:52
Updated: 12/19/2025 20:16
Changes: 11/28/2025 07:52 (61), 11/28/2025 15:04 (1), 11/30/2025 14:18 (7), 12/02/2025 12:01 (2), 12/19/2025 20:16 (11)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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