CVE-2020-10136
IP-in-IP protocol allows a remote, unauthenticated attacker to route arbitrary network traffic
- Published
- Updated
- Reserved
- Assigned by
- certcc
Description
IP-in-IP protocol specifies IP Encapsulation within IP standard (RFC 2003, STD 1) that decapsulate and route IP-in-IP traffic is vulnerable to spoofing, access-control bypass and other unexpected behavior due to the lack of validation to verify network packets before decapsulation and routing.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
- EPSS (exploitation in 30 days)
- 28.5% · top 1.9% of all CVEs (5 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Weakness
Affected products
IETF · RFC2003 - IP Encapsulation within IP
- affected STD 1
What to do
Solution: Customers should apply the latest patch provided by the affected vendor that addresses this issue and prevents unspecified IP-in-IP packets from being processed. Devices manufacturers are urged to disable IP-in-IP in their default configuration and require their customers to explicitly configure IP-in-IP as and when needed.
Workaround: Users can block IP-in-IP packets by filtering IP protocol number 4. Note this filtering is for the IPv4 Protocol (or IPv6 Next Header) field value of 4 and not IP protocol version 4 (IPv4).
References (6)
- VU#636397 (opens in a new tab)x_transferred
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-ipip-dos-kCT9X4 (opens in a new tab)x_transferred
- https://www.digi.com/resources/security (opens in a new tab)x_transferred
- VU#636397 (opens in a new tab)x_transferred
- Security Concerns with IP Tunneling (opens in a new tab)x_transferred
- https://www.kb.cert.org/vuls/id/199397 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-10136)Record last updated .