Used in attacks· fix by 2021-11-17Not scored yet
Realtek AP-Router SDK
CVE-2021-35395
Realtek AP-Router SDK HTTP web server boa contains a buffer overflow vulnerability due to unsafe copies of some overly long parameters submitted in the form that lead to denial-of-service (DoS).
What this means for your business
- It affects Realtek AP-Router SDK. It matters if your company, or a supplier that handles your data, runs it.
- Attackers are already using it. CISA added it to its list of flaws used in real attacks on 3 November 2021.
- FIRST's prediction model gives it a 98% chance of attack attempts being seen in the next 30 days, ranking above 99% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Realtek AP-Router SDK.
- 2If you do, follow CISA's required action below. No patch reference has been published yet.
- 3Treat it as urgent. US federal agencies must fix it by 17 November 2021. That deadline does not apply to private companies, but it shows how seriously CISA takes it.
- 4Because attackers have used it, check the affected systems for signs of a break-in, not only for the update.
Not sure if your company is exposed?
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Required action
Apply updates per vendor instructions.
CISA’s wording, unedited.
Scoring
- CVSS
- Not yet scored
Dates
- Published
- 2021-11-03
- Added to KEV
- 2021-11-03
- Remediation due
- 2021-11-17
- Sources
- CISA KEV