Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2021-27137

83
FAUCET Score

An issue was discovered in router/upnp/src/ssdp.c in DD-WRT before 45724. An unsafe strcpy in the UPnP handling functionality allows an unauthenticated remote attacker to send a request that would overflow an internal fixed buffer. Exploitation requires the DD-WRT user to enable UPnP (which is off by default, and only listens on internal interfaces by default). This occurs in ssdp_msearch (reachable by an M-SEARCH request).

First published: Jul 16, 2026Last modified: Jul 16, 2026

Impacted Technologies

VendorProductVersion(s)CPE
< 45724CPE matchmatch criteria
cpe:2.3:o:dd-wrt:dd-wrt:*:*:*:*:*:*:*:*
>= 0, < 45724CPE match
cpe:2.3:a:dd-wrt:dd-wrt:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

8.1HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
Exploitability Score
2.2
Impact Score
5.9
CvssVersion
3.1

Exploit Intelligence

EPSS Score
16.49%
Probability of exploitation in next 30 days
EPSS Percentile
96.7%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
Added to KEV · Jul 21, 2026
This CVE's current EPSS score of 0.1649 is in the 82nd percentile among its peer group of 8,920 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.2 GitHub mentions.

Media Mentions

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Remediation records are not available for this CVE.

References

cisa.gov / known-exploited-vulnerabilities-catalog
US Government Resource
securityaffairs.com / 193290/uncategorized/iot-botnet-c0xmo-adds-competitor-killing-capability.html
ExploitThird Party Advisory
ssd-disclosure.com / ssd-advisory-dd-wrt-upnp-buffer-overflow
ExploitThird Party Advisory
svn.dd-wrt.com / changeset/45724
Patch
bleepingcomputer.com / news/security/c0xmo-botnet-spreads-via-dd-wrt-router-flaw-kills-rival-malware
ExploitThird Party Advisory
fortinet.com / blog/threat-research/inside-cross-platform-propagation-of-new-gafgyt-variant-c0xmo
Exploit