CVE-2021-3761: Github.com/cloudflare/cfrpki OctoRPKI Lacks Contextual Out-of-bounds Check Vulnerability
HIGHCVE-2021-3761 is a HIGH (CVSS 7.5) octorpki lacks contextual out-of-bounds check vulnerability (CWE-295: Improper Certificate Validation) affecting Github.com/cloudflare/cfrpki libraries in the Go ecosystem. The issue involves octorpki lacks contextual out-of-bounds check when validating rpki roa maxlength values. Remediation is available by upgrading affected packages to version 1.3.0.
CVE-2021-3761 at a Glance
Security Impact
CVSS: 7.5
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
How to Fix CVE-2021-3761
To remediate this vulnerability, upgrade all affected Github.com/cloudflare/cfrpki dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/cloudflare/cfrpki to 1.3.0Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/cloudflare/cfrpkiHow to Check if You Are Affected
To determine whether your application is affected by CVE-2021-3761, inspect your project dependencies for Github.com/cloudflare/cfrpki:
inspect dependencies for github.com/cloudflare/cfrpkiAnalyze the terminal output to locate any version of Github.com/cloudflare/cfrpki in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.3.0), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-295: Improper Certificate Validation, where the product does not validate, or incorrectly validates, a certificate. In Github.com/cloudflare/cfrpki, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2021-3761 Affected Github.com/cloudflare/cfrpki Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/cloudflare/cfrpki
|
Go |
< 1.3.0
|
1.3.0
|
References
Frequently Asked Questions
What is CVE-2021-3761?
Which Github.com/cloudflare/cfrpki versions are affected?
What version fixes CVE-2021-3761?
Is github.com/cloudflare/cfrpki affected?
What is the CVSS score of CVE-2021-3761?
What CWE is associated with CVE-2021-3761?
How can I check Go dependencies for CVE-2021-3761?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-c8xp-8mf3-62h9",
"modified" : "2021-09-03T21:40:39Z",
"published" : "2021-09-07T23:02:18Z",
"aliases" : [ "CVE-2021-3761" ],
"summary" : "OctoRPKI lacks contextual out-of-bounds check when validating RPKI ROA maxLength values",
"details" : "Any CA issuer in the RPKI can trick OctoRPKI prior to https://github.com/cloudflare/cfrpki/commit/a8db4e009ef217484598ba1fd1c595b54e0f6422 into emitting an invalid VRP \"MaxLength\" value, causing RTR sessions to terminate. \n\n### Impact\n\nAn attacker can use this to disable RPKI Origin Validation in a victim network (for example AS 13335 - Cloudflare) prior to launching a BGP hijack which during normal operations would be rejected as \"RPKI invalid\". Additionally, in certain deployments RTR session flapping in and of itself also could cause BGP routing churn, causing availability issues.\n\n### Patches\nhttps://github.com/cloudflare/cfrpki/commit/a8db4e009ef217484598ba1fd1c595b54e0f6422\n\nhttps://github.com/cloudflare/cfrpki/releases/tag/v1.3.0\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Email us at [security@cloudflare.com](security@cloudflare.com)\n",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/cloudflare/cfrpki"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "1.3.0"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/cloudflare/cfrpki/security/advisories/GHSA-c8xp-8mf3-62h9"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-3761"
}, {
"type" : "WEB",
"url" : "https://github.com/cloudflare/cfrpki/pull/90"
}, {
"type" : "WEB",
"url" : "https://github.com/cloudflare/cfrpki/commit/a8db4e009ef217484598ba1fd1c595b54e0f6422"
}, {
"type" : "WEB",
"url" : "https://github.com/cloudflare/cfrpki/releases/tag/v1.3.0"
}, {
"type" : "WEB",
"url" : "https://pkg.go.dev/vuln/GO-2022-0246"
}, {
"type" : "WEB",
"url" : "https://www.debian.org/security/2022/dsa-5041"
}, {
"type" : "PACKAGE",
"url" : "github.com/cloudflare/cfrpki"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-295", "CWE-787" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2021-09-03T21:40:39Z",
"nvd_published_at" : "2021-09-09T14:15:00Z"
}
}