CVE-2026-58469
Description
A flaw was found in GNU Wget. A malicious server could exploit a heap buffer underread vulnerability by providing a specially crafted Metalink document containing a URL with only whitespace characters. This could lead to memory corruption and abnormal program behavior, potentially causing a denial of service.
Statement
Moderate: A heap-buffer-underread in GNU Wget's clean_metalink_string() function, affecting Red Hat Enterprise Linux 8, can be triggered when wget processes a specially crafted Metalink document containing a resource URL consisting only of whitespace characters. This code path is only reachable when Wget's Metalink support is explicitly requested via --input-metalink or --metalink-over-http; it is not exercised during ordinary downloads. Successful exploitation requires a user to invoke Wget's Metalink handling against an attacker-controlled or compromised server. The out-of-bounds byte is read only to decide whether to continue a trim loop and is never returned, logged, or written -- the practical impact is limited to a crash of the wget process (denial of service), not memory corruption or code execution.
Mitigation
Avoid using Wget's Metalink options (--input-metalink and --metalink-over-http) when downloading from untrusted or unverified servers. Since Metalink processing must be explicitly requested, omitting these options avoids the vulnerable code path entirely.
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)
Confidentiality
Technical Impact: Read Memory
An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.
Confidentiality
Technical Impact: Bypass Protection Mechanism
Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.
Other
Technical Impact: Varies by Context
The read operation could produce other undefined or unexpected results.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
