CVE-2021-21540
CVE-2021-21540 is a medium-severity vulnerability in Dell Idrac9 Firmware with a CVSS 3.x base score of 5.9. 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-787.
Key facts
- Severity: Medium (CVSS 3.x base score 5.9)
- CVSS v2: 5.5
- EPSS exploit prediction: 1% (63rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Dell Idrac9 Firmware
- Published:
- Last modified:
Description
Dell EMC iDRAC9 versions prior to 4.40.00.00 contain a stack-based overflow vulnerability. A remote authenticated attacker could potentially exploit this vulnerability to overwrite configuration information by injecting arbitrarily large payload.
Frequently asked questions
- What is CVE-2021-21540?
- Dell EMC iDRAC9 versions prior to 4.40.00.00 contain a stack-based overflow vulnerability. A remote authenticated attacker could potentially exploit this vulnerability to overwrite configuration information by injecting arbitrarily large payload.
- How severe is CVE-2021-21540?
- CVE-2021-21540 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability low.
- Is CVE-2021-21540 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-21540?
- CVE-2021-21540 affects Dell Idrac9 Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-21540?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-21540 published?
- CVE-2021-21540 was published on 2021-04-30 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:dell:idrac9_firmware:*:*:*:*:*:*:*:*
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- CVE-2018-1243 — High (CVSS 7.5): Dell EMC iDRAC6, versions prior to 2.91, iDRAC7/iDRAC8, versions prior to 2.60.60.60 and iDRAC9, versions prior to…
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