CVE-2026-27965

high

Description

Vitess is a database clustering system for horizontal scaling of MySQL. Prior to versions 23.0.3 and 22.0.4, anyone 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. Versions 23.0.3 and 22.0.4 contain a patch. Some workarounds are available. Those who intended to use an external decompressor then 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. Those who did not intend to use an external decompressor, nor an internal one, 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

https://github.com/vitessio/vitess/security/advisories/GHSA-8g8j-r87h-p36x

https://github.com/vitessio/vitess/pull/19460

https://github.com/vitessio/vitess/issues/19459

https://github.com/vitessio/vitess/commit/4c0173293907af9cb942a6683c465c3f1e9fdb5c

Details

Source: Mitre, NVD

Published: 2026-02-26

Updated: 2026-03-02

Risk Information

CVSS v2

Base Score: 9

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 9.9

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Severity: Critical

CVSS v4

Base Score: 8.4

Vector: 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

Severity: High

EPSS

EPSS: 0.00043