Is CVE-2021-31755 exploited in the wild?

Yes. CVE-2021-31755 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

How severe is CVE-2021-31755?

Critical severity, with a CVSS score of 9.8, published 3 November 2021.

Which products and versions are affected?

Tenda AC11 through 02.03.01.104_CN.

Is there a fix for CVE-2021-31755?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2021-31755 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2021-31755?

Check whether you run Tenda Ac11 Router. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2021-31755: Tenda AC11 Router Stack Buffer Overflow Vulnerability

CVE-2021-31755 · Severity: critical · CVSS 9.8 · Exploited in the wild · Published 2021-11-03

Tenda AC11 router devices are vulnerable to a stack-based buffer overflow in the /goform/setmac endpoint. An attacker can exploit this by sending a specially crafted POST request to execute arbitrary code on the system.

Vendors: Tenda.

Quick answers

Is CVE-2021-31755 exploited in the wild?: Yes. CVE-2021-31755 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.
How severe is CVE-2021-31755?: Critical severity, with a CVSS score of 9.8, published 3 November 2021.
Which products and versions are affected?: Tenda AC11 through 02.03.01.104_CN.
Is there a fix for CVE-2021-31755?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2021-31755 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2021-31755?: Check whether you run Tenda Ac11 Router. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Affected products

Tenda AC11 through 02.03.01.104_CN

Timeline

2021-05-07: disclosed: NVD Published Date
2021-11-03: kev added: Date added to CISA Known Exploited Vulnerabilities Catalog
2021-11-17: other: CISA KEV due date for remediation

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.