CVE-2026-42154highCWE-400CWE-770CWE-789

CVE-2026-42154: high-severity vulnerability in prometheus

Prometheus: remote read endpoint allows denial of service via crafted snappy payload

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41Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 7.5epss 0.8%
from disclosure to weapon11 days
Published on NVDMay 4
1st PoC+11d
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
prometheus · prometheus
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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