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Fencer Intel
medium 5.5

CVE-2021-1128 json

Cisco IOS XR Software Unauthorized Information Disclosure Vulnerability

published 5y ago modified 4mo ago also EUVD-2021-6595

cvss
5.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 29%
public exploits
0
none known

Summary

A vulnerability in the CLI parser of Cisco IOS XR Software could allow an authenticated, local attacker to view more information than their privileges allow. The vulnerability is due to insufficient application of restrictions during the execution of a specific command. An attacker could exploit this vulnerability by using a specific command at the command line. A successful exploit could allow the attacker to obtain sensitive information within the configuration that otherwise might not have been accessible beyond the privileges of the invoking user.

Patch / fix

  • cisco ios_xr 7.1.2

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2y ago

Exploit prediction

0.36% chance of exploitation in the next 30 days, higher than 29% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD 2.0 2.1 AV:L/AC:L/Au:N/C:P/I:N/A:N

Affected products

  • Cisco Cisco IOS XR Software

Classification

Weakness
  • CWE-201 Insertion of Sensitive Information Into Sent Data
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.