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CVE-2006-4650
Cisco IOS 12.0, 12.1, and 12.2, when GRE IP tunneling is used and the RFC2784 compliance fixes are missing, does not verify the offset…
Low2.6EPSS 3.2%
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
Cisco IOS 12.0, 12.1, and 12.2, when GRE IP tunneling is used and the RFC2784 compliance fixes are missing, does not verify the offset field of a GRE packet during decapsulation, which leads to an integer overflow that references data from incorrect memory locations, which allows remote attackers to inject crafted packets into the routing queue, possibly bypassing intended router ACLs.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 2.0 | Low2.6 | AV:N/AC:H/Au:N/C:P/I:N/A:N |
- EPSS (exploitation in 30 days)
- 3.2% · top 12% of all CVEs (5 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 2.6.
Weakness
- n/a
Affected products
n/a
- affected n/a
References (11)
- ADV-2006-3502 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
- 1016799 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
- 28590 (opens in a new tab)vdb-entryx_refsource_OSVDBx_transferred
- 20060906 Cisco IOS GRE issue (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- http://www.phenoelit.de/stuff/CiscoGRE.txt (opens in a new tab)x_refsource_MISCx_transferred
- 21783 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- 1526 (opens in a new tab)third-party-advisoryx_refsource_SREASONx_transferred
- 19878 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- 20060906 Cisco IOS GRE Decapsulation Vulnerability (opens in a new tab)vendor-advisoryx_refsource_CISCOx_transferred
- oval:org.mitre.oval:def:5713 (opens in a new tab)vdb-entrysignaturex_refsource_OVALx_transferred
- cisco-ios-gre-acl-bypass(28786) (opens in a new tab)vdb-entryx_refsource_XFx_transferred
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)
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[](https://trackcve.app/cve/CVE-2006-4650)Record last updated .