CVE-2026-27965: Vitess.io/vitess Vitess Users With Backup Storage Vulnerability

HIGH
Advisory Identifier: GHSA-8g8j-r87h-p36x
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CWE-78
Published
Advisory Summary

CVE-2026-27965 is a HIGH vitess users with backup storage vulnerability (CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')) affecting Vitess.io/vitess libraries in the Go ecosystem. The issue involves vitess users with backup storage access can gain unauthorized access to production deployment environments. Remediation is available in the latest vendor maintenance releases.

CVE-2026-27965 at a Glance

CVE Identifier CVE-2026-27965
GHSA Identifier GHSA-8g8j-r87h-p36x
Severity HIGH
CVSS v3.1 Base Score N/A
CWE Classification CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Affected Product Vitess.io/vitess
Package Ecosystem Go
Published Date
Last Updated

How to Fix CVE-2026-27965

To remediate this vulnerability, upgrade all affected Vitess.io/vitess dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

vitess.io/vitess fixed: Latest secure release 
Upgrade vitess.io/vitess to Latest secure release
Verify Direct and Transitive Dependencies

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

inspect dependencies for vitess.io/vitess

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-27965, inspect your project dependencies for Vitess.io/vitess:

inspect dependencies for vitess.io/vitess

Analyze the terminal output to locate any version of Vitess.io/vitess 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: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection'), where the product constructs all or part of an os command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended os command when it is sent to a downstream component. In Vitess.io/vitess, 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

### Impact Any user with read/write access to the backup storage location (e.g. an S3 bucket) can manipulate backup manifest files so that arbitrary code is later executed when that backup is restored. This can be used to provide that attacker with unintended/unauthorized access to the production deployment environment — allowing them to access information available in that environment as well as run any additional arbitrary commands there. ### Patches Fixes are expected to be released with versions v23.0.3 and v22.0.4 See fix commit at https://github.com/vitessio/vitess/commit/4c0173293907af9cb942a6683c465c3f1e9fdb5c ### Workarounds If maintainers *intended* to use an external decompressor then they can always specify that decompressor command in the `--external-decompressor` flag value for `vttablet` and `vtbackup`. That then overrides any value specified in the manifest file. If maintainers did *not intend* to use an external decompressor, nor an internal one, then they can specify a value such as `cat` or `tee` in the `--external-decompressor` flag value for `vttablet` and `vtbackup` to ensure that a harmless command is always used. ### References Users can read more about the issue here: https://github.com/vitessio/vitess/issues/19459

CVE-2026-27965 Affected Vitess.io/vitess Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
vitess.io/vitess
golang/vitess.io/vitess
Go
≤ 0.23.2

References

GitHub Advisory / Wiki ADVISORY
https://github.com/vitessio/vitess/security/advisories/GHSA-8g8j-r87h-p36x
NVD — CVE-2026-27965 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-27965
Vitess.io/vitess Source Repository REPOSITORY
https://github.com/vitessio/vitess/issues/19459
Vitess.io/vitess Source Repository REPOSITORY
https://github.com/vitessio/vitess/pull/19460
Security Fix Commit FIX COMMIT
https://github.com/vitessio/vitess/commit/4c0173293907af9cb942a6683c465c3f1e9fdb5c
Vitess.io/vitess Source Repository REPOSITORY
https://github.com/vitessio/vitess

Frequently Asked Questions

What is CVE-2026-27965?
CVE-2026-27965 is a security vulnerability in Vitess.io/vitess involving Vitess users with backup storage access can gain unauthorized access to production deployment environments under CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection').
Which Vitess.io/vitess versions are affected?
Affected versions include releases prior to current release patches across affected packages: vitess.io/vitess.
What version fixes CVE-2026-27965?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is vitess.io/vitess affected?
Yes, vitess.io/vitess is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What CWE is associated with CVE-2026-27965?
CVE-2026-27965 is classified under CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') (The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.).
How can I check Go dependencies for CVE-2026-27965?
Run the dependency tree command: 'inspect dependencies for vitess.io/vitess'. 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-8g8j-r87h-p36x",
  "modified" : "2026-02-26T22:50:37Z",
  "published" : "2026-02-26T22:50:37Z",
  "aliases" : [ "CVE-2026-27965" ],
  "summary" : "Vitess users with backup storage access can gain unauthorized access to production deployment environments",
  "details" : "### Impact\n\nAny user with read/write access to the backup storage location (e.g. an S3 bucket) can manipulate backup manifest files so that arbitrary code is later executed when that backup is restored. This can be used to provide that attacker with unintended/unauthorized access to the production deployment environment — allowing them to access information available in that environment as well as run any additional arbitrary commands there.\n\n### Patches\nFixes are expected to be released with versions v23.0.3 and v22.0.4\nSee fix commit at https://github.com/vitessio/vitess/commit/4c0173293907af9cb942a6683c465c3f1e9fdb5c\n\n### Workarounds\n\nIf maintainers *intended* to use an external decompressor then they can always specify that decompressor command in the `--external-decompressor` flag value for `vttablet` and `vtbackup`. That then overrides any value specified in the manifest file.\n\nIf maintainers did *not intend* to use an external decompressor, nor an internal one, then they can specify a value such as `cat` or `tee` in the `--external-decompressor` flag value for `vttablet` and `vtbackup` to ensure that a harmless command is always used. \n\n### References\n\nUsers can read more about the issue here: https://github.com/vitessio/vitess/issues/19459",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:L/SC:L/SI:L/SA:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "vitess.io/vitess"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "0.23.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/vitessio/vitess/security/advisories/GHSA-8g8j-r87h-p36x"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-27965"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/vitessio/vitess/issues/19459"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/vitessio/vitess/pull/19460"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/vitessio/vitess/commit/4c0173293907af9cb942a6683c465c3f1e9fdb5c"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/vitessio/vitess"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-78" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-02-26T22:50:37Z",
    "nvd_published_at" : "2026-02-26T02:16:23Z"
  }
}