What is CVE-2021-34771?

CVE-2021-34771 is a medium-severity vulnerability in Cisco iOS Xr Software, classified under Insertion of Sensitive Information into Sent Data. CVSS score: 5.5/10. Published 2021-09-09.

How severe is CVE-2021-34771?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Information disclosure in Cisco iOS Xr Software

CVE-2021-34771

A vulnerability in the Cisco IOS XR Software CLI could allow an authenticated, local attacker to view more information than their privileges allow. This vulnerability is due to insufficient application of restrictions during the execution of a specific command. An attacker could exploit this vulnerability by running a specific command. A successful exploit could allow the attacker to view sensitive configuration information that their privileges might not otherwise allow them to access.

Published 2021-09-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (15.9th percentile), scored 2026-10-03.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 16th percentile — 15.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-in… (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2021-34771?: CVE-2021-34771 is a medium-severity vulnerability in Cisco iOS Xr Software, classified under Insertion of Sensitive Information into Sent Data. CVSS score: 5.5/10. Published 2021-09-09.
How severe is CVE-2021-34771?: Medium severity. CVSS v3 base score is 5.5 out of 10.