CVE-2026-63949: Software Security Vulnerability Vulnerability

UNKNOWN
Advisory Identifier: GHSA-3qfr-7vgq-2884
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Advisory Summary

CVE-2026-63949 is a security vulnerability vulnerability (General Security Weakness) affecting Software libraries in the Maven ecosystem. Remediation is available in the latest vendor maintenance releases.

CVE-2026-63949 at a Glance

CVE Identifier CVE-2026-63949
GHSA Identifier GHSA-3qfr-7vgq-2884
Severity N/A
CVSS v3.1 Base Score N/A
CWE Classification General Security Weakness
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

How to Fix CVE-2026-63949

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.

Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-63949, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

Analyze 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 General Security Weakness. 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

In the Linux kernel, the following vulnerability has been resolved: auxdisplay: line-display: fix OOB read on zero-length message_store() linedisp_display() unconditionally reads msg[count - 1] before checking whether count is zero, so a write of zero bytes to the message sysfs attribute hits msg[-1]: write(fd, "", 0); -> message_store(..., buf, count=0) -> linedisp_display(linedisp, buf, count=0) -> msg[count - 1] == '\n' ; OOB read The kernfs write buffer for that store is a 1-byte allocation (kernfs_fop_write_iter() does kmalloc(len + 1) with len == 0), so msg[-1] is a 1-byte read before the slab object. On a KASAN-enabled kernel this trips an out-of-bounds report and panics; on stock kernels it silently reads adjacent slab data and, if that byte happens to be '\n', the following count-- wraps ssize_t 0 to -1 and is then passed to kmemdup_nul(). linedisp_display() is reached from the message_store() sysfs callback (drivers/auxdisplay/line-display.c message attribute, mode 0644) and from the in-tree initial-message setup with count == -1, so the OOB path is only userspace-triggerable via zero-byte writes; vfs_write() does not short-circuit on count == 0 and kernfs_fop_write_iter() dispatches the store callback regardless. Guard the trailing-newline trim with a count check. The existing if (!count) block then takes the clear-display path unchanged. Affects every auxdisplay driver that registers via linedisp_register() / linedisp_attach(): ht16k33, max6959, img-ascii-lcd, seg-led-gpio.

References

NVD — CVE-2026-63949 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-63949
git.kernel.org/stable/c/197476b126... WEB
https://git.kernel.org/stable/c/197476b126010bac1b3199833c6966cd6f54c2a9
git.kernel.org/stable/c/3859960dae... WEB
https://git.kernel.org/stable/c/3859960daeb9b7b39b9847b5b0113bc6081eb735
git.kernel.org/stable/c/6ad4f75ef9... WEB
https://git.kernel.org/stable/c/6ad4f75ef9f3372fce8cad494e789ac6a5507bef
git.kernel.org/stable/c/8776032fe9... WEB
https://git.kernel.org/stable/c/8776032fe989a9b5fc77f2de5e03e4adb44c630e
git.kernel.org/stable/c/a7511dcd9d... WEB
https://git.kernel.org/stable/c/a7511dcd9dd4bc55d123f9b800c8a4ed2662e5c6
git.kernel.org/stable/c/ca5b078194... WEB
https://git.kernel.org/stable/c/ca5b0781946d5083ceafa752141f47f085853620

Frequently Asked Questions

What is CVE-2026-63949?
CVE-2026-63949 is a security vulnerability in Software classified as a security vulnerability vulnerability under General Security Weakness.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-63949?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What CWE is associated with CVE-2026-63949?
CVE-2026-63949 is classified under General Security Weakness.
How can I check Maven dependencies for CVE-2026-63949?
Run the dependency tree command: 'mvn dependency:tree'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-3qfr-7vgq-2884",
  "modified" : "2026-07-19T18:31:47Z",
  "published" : "2026-07-19T18:31:47Z",
  "aliases" : [ "CVE-2026-63949" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nauxdisplay: line-display: fix OOB read on zero-length message_store()\n\nlinedisp_display() unconditionally reads msg[count - 1] before\nchecking whether count is zero, so a write of zero bytes to the\nmessage sysfs attribute hits msg[-1]:\n\n\twrite(fd, \"\", 0);\n\n\t-> message_store(..., buf, count=0)\n\t   -> linedisp_display(linedisp, buf, count=0)\n\t      -> msg[count - 1] == '\\n'  ; OOB read\n\nThe kernfs write buffer for that store is a 1-byte allocation\n(kernfs_fop_write_iter() does kmalloc(len + 1) with len == 0),\nso msg[-1] is a 1-byte read before the slab object. On a\nKASAN-enabled kernel this trips an out-of-bounds report and\npanics; on stock kernels it silently reads adjacent slab data\nand, if that byte happens to be '\\n', the following count--\nwraps ssize_t 0 to -1 and is then passed to kmemdup_nul().\n\nlinedisp_display() is reached from the message_store() sysfs\ncallback (drivers/auxdisplay/line-display.c message attribute,\nmode 0644) and from the in-tree initial-message setup with\ncount == -1, so the OOB path is only userspace-triggerable via\nzero-byte writes; vfs_write() does not short-circuit on\ncount == 0 and kernfs_fop_write_iter() dispatches the store\ncallback regardless.\n\nGuard the trailing-newline trim with a count check. The\nexisting if (!count) block then takes the clear-display path\nunchanged.\n\nAffects every auxdisplay driver that registers via\nlinedisp_register() / linedisp_attach(): ht16k33, max6959,\nimg-ascii-lcd, seg-led-gpio.",
  "severity" : [ ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-63949"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/197476b126010bac1b3199833c6966cd6f54c2a9"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/3859960daeb9b7b39b9847b5b0113bc6081eb735"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/6ad4f75ef9f3372fce8cad494e789ac6a5507bef"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/8776032fe989a9b5fc77f2de5e03e4adb44c630e"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/a7511dcd9dd4bc55d123f9b800c8a4ed2662e5c6"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/ca5b0781946d5083ceafa752141f47f085853620"
  } ],
  "database_specific" : {
    "cwe_ids" : [ ],
    "severity" : null,
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-07-19T16:17:13Z"
  }
}