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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-16599 Detail

Description

GNU wget is vulnerable to denial of service in its FTP OPIE/S-KEY authentication functionality. The server-supplied sequence number from the FTP challenge line is used as an iteration count for an MD5 key-derivation loop without any upper bound validation. A malicious FTP server or a network attacker positioned to intercept FTP traffic can send a crafted OPIE challenge with a sequence number near INT_MAX, causing wget to perform up to approximately 2.1 billion MD5 computations and suspend for some time. The --timeout option does not mitigate this because it applies only to network I/O, not CPU computation. This issue was fixed in commit e9697d98e7249b0f68a6be040a4f3dcc5bc101fa


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  CERT.PL
CVSS-B 5.1 MEDIUM
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://cert.pl/en/posts/2026/08/CVE-2026-16599 CERT.PL
https://gitlab.com/gnuwget/wget CERT.PL
https://gitlab.com/gnuwget/wget/-/commit/e9697d98e7249b0f68a6be040a4f3dcc5bc101fa CERT.PL

Weakness Enumeration

CWE-ID CWE Name Source
CWE-606 Unchecked Input for Loop Condition CERT.PL  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-16599
NVD Published Date:
08/25/2026
NVD Last Modified:
08/25/2026
Source:
CERT.PL