CVE-2021-27137: DD-WRT Stack-Based Buffer Overflow Vulnerability
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation as urgent.
DD-WRT contains a stack-based buffer overflow vulnerability that could allow an unauthenticated attacker to overflow an internal buffer used by UPnP and trigger a code execution vulnerability.
CSIRTS triage
- What
- DD-WRT contains a stack-based buffer overflow vulnerability that could allow an unauthenticated attacker to execute code.
- Who is affected
- All installations of DD-WRT are affected.
- Urgency
- Remediation is critical due to active exploitation and the potential for remote code execution.
- Action
- Apply the latest patch for DD-WRT.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2021-27137
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Exploitation confirmedCVE-2021-27137Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 97% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2021-27137 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
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