CVE-2021-1128
CVE-2021-1128 is a medium-severity vulnerability in Cisco Ios Xr with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-201.
Key facts
- Severity: Medium (CVSS 3.x base score 5.5)
- CVSS v2: 2.1
- EPSS exploit prediction: 0% (26th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-201
- Affected product: Cisco Ios Xr
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is CVE-2021-1128?
- 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.
- How severe is CVE-2021-1128?
- CVE-2021-1128 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2021-1128 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-1128?
- CVE-2021-1128 primarily affects Cisco Ios Xr. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-1128?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-1128 published?
- CVE-2021-1128 was published on 2021-02-04 and last updated on 2026-06-17.
References
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-infodisc-4mtm9Gyt
Affected products (3)
- cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xr:7.2.0:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xr:7.3.0:*:*:*:*:*:*:*
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