CVE-2026-27749: Software Security Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-w8px-r6g2-r3wp
Share
CVSS 7.8
CWE-502
Published
Advisory Summary

CVE-2026-27749 is a HIGH (CVSS 7.8) security vulnerability vulnerability (CWE-502: Deserialization of Untrusted Data) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-27749 at a Glance

CVE Identifier CVE-2026-27749
GHSA Identifier GHSA-w8px-r6g2-r3wp
Severity HIGH
CVSS v3.1 Base Score 7.8
CWE Classification CWE-502: Deserialization of Untrusted Data
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 7.8

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:U/C:H/I:H/A:H).

Attack Vector Local (AV:L)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-27749

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-2026-27749, 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 CWE-502: Deserialization of Untrusted Data, where the product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid. 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

Avira Internet Security contains a deserialization of untrusted data vulnerability in the System Speedup component. The Avira.SystemSpeedup.RealTimeOptimizer.exe process, which runs with SYSTEM privileges, deserializes data from a file located in C:\\ProgramData using .NET BinaryFormatter without implementing input validation or deserialization safeguards. Because the file can be created or modified by a local user in default configurations, an attacker can supply a crafted serialized payload that is deserialized by the privileged process, resulting in arbitrary code execution as SYSTEM.

References

NVD — CVE-2026-27749 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-27749
blog.quarkslab.com/avira-deserialize-d... WEB
https://blog.quarkslab.com/avira-deserialize-delete-and-escalate-the-proper-way-to-use-an-av.html
support.avira.com/hc/en-us/articles/3... WEB
https://support.avira.com/hc/en-us/articles/360010656158-Current-Avira-versions
Software Security Information SECURITY
https://www.avira.com/en/internet-security
Software Security Information SECURITY
https://www.gendigital.com/us/en/contact-us/security-advisories
Software Security Information SECURITY
https://www.vulncheck.com/advisories/avira-internet-security-system-speedup-insecure-deserialization

Frequently Asked Questions

What is CVE-2026-27749?
CVE-2026-27749 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-502: Deserialization of Untrusted Data.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-27749?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-27749?
CVE-2026-27749 has a CVSS v3.1 base score of 7.8 (HIGH) with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2026-27749?
CVE-2026-27749 is classified under CWE-502: Deserialization of Untrusted Data (The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.).
How can I check Maven dependencies for CVE-2026-27749?
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-w8px-r6g2-r3wp",
  "modified" : "2026-04-01T15:30:56Z",
  "published" : "2026-03-05T15:30:36Z",
  "aliases" : [ "CVE-2026-27749" ],
  "details" : "Avira Internet Security contains a deserialization of untrusted data vulnerability in the System Speedup component. The Avira.SystemSpeedup.RealTimeOptimizer.exe process, which runs with SYSTEM privileges, deserializes data from a file located in C:\\\\ProgramData using .NET BinaryFormatter without implementing input validation or deserialization safeguards. Because the file can be created or modified by a local user in default configurations, an attacker can supply a crafted serialized payload that is deserialized by the privileged process, resulting in arbitrary code execution as SYSTEM.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-27749"
  }, {
    "type" : "WEB",
    "url" : "https://blog.quarkslab.com/avira-deserialize-delete-and-escalate-the-proper-way-to-use-an-av.html"
  }, {
    "type" : "WEB",
    "url" : "https://support.avira.com/hc/en-us/articles/360010656158-Current-Avira-versions"
  }, {
    "type" : "WEB",
    "url" : "https://www.avira.com/en/internet-security"
  }, {
    "type" : "WEB",
    "url" : "https://www.gendigital.com/us/en/contact-us/security-advisories"
  }, {
    "type" : "WEB",
    "url" : "https://www.vulncheck.com/advisories/avira-internet-security-system-speedup-insecure-deserialization"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-502" ],
    "severity" : "HIGH",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-03-05T15:16:11Z"
  }
}