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Fencer Intel
high 8.8

CVE-2020-3400 json

Cisco IOS XE Software Web UI Authorization Bypass Vulnerability

published 6y ago modified 4mo ago also EUVD-2020-24671

cvss
8.8
version 3.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.0%
EPSS 1.0% chance of exploitation in 30 days, percentile 62%
public exploits
0
none known

Summary

A vulnerability in the web UI feature of Cisco IOS XE Software could allow an authenticated, remote attacker to utilize parts of the web UI for which they are not authorized.The vulnerability is due to insufficient authorization of web UI access requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to the web UI. A successful exploit could allow the attacker to utilize parts of the web UI for which they are not authorized. This could allow a Read-Only user to perform actions of an Admin user.

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
last yr.

Exploit prediction

0.98% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.0 8.8 CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 6.5 AV:N/AC:L/Au:S/C:P/I:P/A:P

Affected products

  • Cisco Cisco IOS XE Software

Classification

Weakness
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.