CVE-2021-4242
CVE-2021-4242 is a medium-severity vulnerability in Sapido Br270n Firmware with a CVSS 3.x base score of 6.3. 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-78.
Key facts
- Severity: Medium (CVSS 3.x base score 6.3)
- EPSS exploit prediction: 3% (86th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-78
- Affected product: Sapido Br270n Firmware
- Published:
- Last modified:
Description
A vulnerability was found in Sapido BR270n, BRC76n, GR297 and RB1732 and classified as critical. Affected by this issue is some unknown functionality of the file ip/syscmd.htm. The manipulation leads to os command injection. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-214592.
Frequently asked questions
- What is CVE-2021-4242?
- A vulnerability was found in Sapido BR270n, BRC76n, GR297 and RB1732 and classified as critical. Affected by this issue is some unknown functionality of the file ip/syscmd.htm. The manipulation leads to os command injection. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-214592.
- How severe is CVE-2021-4242?
- CVE-2021-4242 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
- Is CVE-2021-4242 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-4242?
- CVE-2021-4242 primarily affects Sapido Br270n Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-4242?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-4242 published?
- CVE-2021-4242 was published on 2022-11-30 and last updated on 2026-06-17.
References
- https://blog.csdn.net/qq_44159028/article/details/114590267
- https://github.com/smallpiggy/Sapido--rce/blob/main/Sapido%E8%B7%AF%E7%94%B1%E5%99%A8-rce.py
- https://vuldb.com/?id.214592
Affected products (4)
- cpe:2.3:o:sapido:br270n_firmware:2.1.03:*:*:*:*:*:*:*
- cpe:2.3:o:sapido:brc76n_firmware:2.1.03:*:*:*:*:*:*:*
- cpe:2.3:o:sapido:gr297n_firmware:2.1.3:*:*:*:*:*:*:*
- cpe:2.3:o:sapido:rb-1732_firmware:2.0.43:*:*:*:*:*:*:*
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