CVE-2026-39244
Description
A flaw was found in adm-zip. A remote attacker can exploit this vulnerability by providing a specially crafted ZIP file. The file's header can be manipulated to declare an extremely large uncompressed size, causing the application to allocate an excessive amount of memory. This excessive memory allocation can lead to an immediate process crash, resulting in a Denial of Service (DoS) for any application processing untrusted ZIP files with adm-zip.
Statement
A denial of service flaw exists in adm-zip, affecting applications that process untrusted ZIP archives. A specially crafted ZIP file with a manipulated uncompressed size header can lead to excessive memory allocation, causing an immediate process crash. This vulnerability can be exploited remotely without authentication, as the memory allocation occurs before CRC validation.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Amplification; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)
System resources, CPU and memory, can be quickly consumed. This can lead to poor system performance or system crash.
Frequently Asked Questions
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