CVE-2026-63921: Software Security Vulnerability Vulnerability
HIGHCVE-2026-63921 is a HIGH (CVSS 8.8) security vulnerability vulnerability (CWE-862: Missing Authorization) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product does not perform an authorization check when an actor attempts to access a resource or perform an action.. Remediation is available in the latest vendor maintenance releases.
CVE-2026-63921 at a Glance
Security Impact
CVSS: 8.8
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H).
How to Fix CVE-2026-63921
To remediate this vulnerability, upgrade all affected Software dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
mvn dependency:treeHow to Check if You Are Affected
To determine whether your Java application is affected by CVE-2026-63921, inspect your build dependencies using the Maven Dependency Plugin:
mvn dependency:treeAnalyze the terminal output to locate any version of Software in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.
Note: The mvn dependency:tree command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-862: Missing Authorization, where the product does not perform an authorization check when an actor attempts to access a resource or perform an action. In Software, 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
References
Frequently Asked Questions
What is CVE-2026-63921?
Which Software versions are affected?
What version fixes CVE-2026-63921?
What is the CVSS score of CVE-2026-63921?
What CWE is associated with CVE-2026-63921?
How can I check Maven dependencies for CVE-2026-63921?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-c82w-wxq7-hwv4",
"modified" : "2026-07-20T15:31:51Z",
"published" : "2026-07-19T18:31:46Z",
"aliases" : [ "CVE-2026-63921" ],
"details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nip6: vti: Use ip6_tnl.net in vti6_siocdevprivate().\n\nAfter patch 1/2 in this series, vti6_update() unlinks and relinks\nthe tunnel through t->net. vti6_siocdevprivate() still uses\ndev_net(dev) for the collision lookup. For a tunnel moved through\nIFLA_NET_NS_FD, dev_net(dev) is the new netns, not t->net.\n\nSIOCCHGTUNNEL on a migrated tunnel then runs:\n\n net = dev_net(dev) /* migrated netns */\n t = vti6_locate(net, &p1, false) /* misses target in t->net */\n ...\n t = netdev_priv(dev)\n vti6_update(t, &p1, false) /* mutates t->net's hash */\n\nA caller in the migrated netns picks params that match a tunnel\nin the creation netns. The lookup in dev_net(dev) finds nothing.\nvti6_update() prepends the migrated tunnel at the head of the\ncreation netns hash bucket for those params. Later lookups in\nthe creation netns resolve to the migrated device. xfrm receive\ndelivers the matched packets through a device the caller controls.\n\nReachable from an unprivileged user namespace (unshare --user\n--map-root-user --net). Cross tenant scope on container hosts.\n\nSwitch the SIOCCHGTUNNEL path on a non fallback device to use\nt->net for the lookup. The lookup now matches the netns\nvti6_update() operates on.\n\nAlso add ns_capable(self->net->user_ns, CAP_NET_ADMIN) before\nthe lookup. The check at the top of the case is against\ndev_net(dev)->user_ns, which after migration is the attacker's\nnetns. A caller there can pick params absent from self->net,\nthe lookup returns NULL, t becomes self, and vti6_update()\ninserts the device into the creation netns hash. The new check\nrequires CAP_NET_ADMIN in the creation netns user_ns too.\n\nSIOCADDTUNNEL and SIOCCHGTUNNEL on the fallback device keep\ndev_net(dev), which equals init_net there.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"
} ],
"affected" : [ ],
"references" : [ {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-63921"
}, {
"type" : "WEB",
"url" : "https://git.kernel.org/stable/c/1acfb7d9c6fc7e209ed7789392697e97e03edd33"
}, {
"type" : "WEB",
"url" : "https://git.kernel.org/stable/c/44d2ff7d2178503b93151140a45dfa2ad49c9906"
}, {
"type" : "WEB",
"url" : "https://git.kernel.org/stable/c/596f6354c96a891e58c04a09cbfb7b0d1ec00dab"
}, {
"type" : "WEB",
"url" : "https://git.kernel.org/stable/c/853f6ea482dfcd3404bbef458ab4d68364eed838"
}, {
"type" : "WEB",
"url" : "https://git.kernel.org/stable/c/8b484efd5cb4eeef9021a661e198edc5349dacf6"
}, {
"type" : "WEB",
"url" : "https://git.kernel.org/stable/c/94ff740a7f9ef5c010784a325dca00cbf228f941"
}, {
"type" : "WEB",
"url" : "https://git.kernel.org/stable/c/d2236348414bdd6558385f35aa7fdc9bf5634011"
}, {
"type" : "WEB",
"url" : "https://git.kernel.org/stable/c/df42ac708acc3399bbb6dc5ca16e0540adda7bbf"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-862" ],
"severity" : "HIGH",
"github_reviewed" : false,
"github_reviewed_at" : null,
"nvd_published_at" : "2026-07-19T16:17:10Z"
}
}