CVE-2026-20125
Cisco HTTP Server Remote Authentication Bypass Denial of Service Vulnerability
Description
A vulnerability in the HTTP Server feature of Cisco IOS Software and Cisco IOS XE Software Release 3E could allow an authenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper validation of user-supplied input. An attacker could exploit this vulnerability by sending malformed HTTP requests to an affected device. A successful exploit could allow the attacker to cause a watchdog timer to expire and the device to reload, resulting in a DoS condition. To exploit this vulnerability, the attacker must have a valid user account.
INFO
Published Date :
March 25, 2026, 4:16 p.m.
Last Modified :
March 25, 2026, 4:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-20125
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update Cisco IOS Software and IOS XE Software to resolved versions.
- Ensure proper input validation mechanisms are in place.
- Restrict HTTP server access to authorized users only.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-20125.
| URL | Resource |
|---|---|
| https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-http-dos-sbv8XRpL |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-20125 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-20125
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-20125 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-20125 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Mar. 25, 2026
Action Type Old Value New Value Added Description A vulnerability in the HTTP Server feature of Cisco IOS Software and Cisco IOS XE Software Release 3E could allow an authenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper validation of user-supplied input. An attacker could exploit this vulnerability by sending malformed HTTP requests to an affected device. A successful exploit could allow the attacker to cause a watchdog timer to expire and the device to reload, resulting in a DoS condition. To exploit this vulnerability, the attacker must have a valid user account. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H Added CWE CWE-228 Added Reference https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-http-dos-sbv8XRpL