SECUFOCUSNOW
Home›CVE index›CVE-2026-42154
Review reviewHigh

CVE-2026-42154

prometheus prometheus, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9

Prometheus is an open-source monitoring system and time series database. Prior to versions 3.5.3 and 3.11.3, the remote read endpoint (/api/v1/read) does not validate the declared decoded length in a snappy-compressed request body before allocating memory. An unauthenticated attacker can send a small payload that causes a huge heap allocation per request. Under concurrent load this can exhaust available memory and crash the Prometheus process. This issue has been patched in versions 3.5.3 and 3.11.3.

CVSS
7.5
EPSS
0.81%
53.5% percentile
CISA KEV
Not listed
Published
2026.05.05
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.81%
Technical severityCVSS 7.5

Vulnerability overview

Prometheus is an open-source monitoring system and time series database. Prior to versions 3.5.3 and 3.11.3, the remote read endpoint (/api/v1/read) does not validate the declared decoded length in a snappy-compressed request body before allocating memory. An unauthenticated attacker can send a small payload that causes a huge heap allocation per request. Under concurrent load this can exhaust available memory and crash the Prometheus process. This issue has been patched in versions 3.5.3 and 3.11.3.

Affected product and versions

Product
prometheus prometheus, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9
Affected versions
>= < 3.5.3, >= >= 3.6.0, < 3.11.3, < 3.5.3, >= 3.6.0 < 3.11.3
Fixed versions
3.5.3, 3.11.3

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that prometheus prometheus, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
CWE-400, CWE-770, CWE-789