CVE-2026-22184
Description
A flaw was found in zlib. A global buffer overflow vulnerability exists in the untgz utility, specifically within the TGZfname() function. This flaw allows an attacker to provide an archive name longer than 1024 bytes, leading to an out-of-bounds write. This can result in memory corruption, denial of service, and potentially arbitrary code execution on the affected system.
Statement
This vulnerability is rated Important rather than Critical because, although it allows a classic global buffer overflow that can compromise the availability of the affected process and potentially impact integrity, it does not meet the criteria for easy, remote, unauthenticated system compromise. The flaw is confined to the untgz command-line utility and is triggered only through attacker-controlled command-line arguments, not through automatic processing of network data or background services. Exploitation therefore generally requires local access or a cooperating application or script that passes untrusted input to untgz, which places it outside the class of wormable or directly remote exploits. While the vulnerability can reliably cause a denial of service and may lead to code execution under specific build and runtime conditions, such outcomes are highly dependent on compiler hardening, memory layout, and execution context, making exploitation less straightforward than required for a Critical rating.
Mitigation
To mitigate this vulnerability, avoid using the `untgz` utility with untrusted archive names or from untrusted sources. System administrators should ensure that any automated processes or user interactions involving `untgz` validate the length of archive names to prevent triggering the buffer overflow. If the `untgz` utility is not essential for system operation, consider restricting its execution permissions or removing the package that provides it, if applicable.
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 | 8.6 | 7.8 | 8.6 |
| Attack Vector | Network | Local | Network |
| Attack Complexity | Low | Low | Low |
| Privileges Required | None | Low | None |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | Low | High | Low |
| Integrity Impact | Low | High | Low |
| Availability Impact | High | High | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Modify Memory; Execute Unauthorized Code or Commands
Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of the product's implicit security policy. This can often be used to subvert any other security service.
Availability
Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU)
Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the product into an infinite loop.
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