# CVE-2026-42154: Prometheus: remote read endpoint allows denial of service via crafted snappy payload > Unauthenticated attackers can crash Prometheus by sending crafted snappy payloads to the remote read endpoint, causing memory exhaustion. - **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 4 May 2026 - **Updated:** 10 Sep 2026 - **Also known as:** AZL-86607, BIT-prometheus-2026-42154, CLEANSTART-2026-CA81083, CLEANSTART-2026-DF38360, CLEANSTART-2026-DV32508, CLEANSTART-2026-GD06163, CLEANSTART-2026-JB79169, CLEANSTART-2026-KT10407, CLEANSTART-2026-PK17685, CLEANSTART-2026-XX38333, DEBIAN-CVE-2026-42154, ECHO-413e-6564-12cd, GHSA-8rm2-7qqf-34qm, GO-2026-5264, MINI-23xg-538c-xj5f, MINI-24w2-qhqw-rp72, MINI-27pg-c34w-ph63, MINI-29rc-phqq-wqcm, MINI-2f34-96j3-w8mh, MINI-2hm8-h2f8-mq8r, MINI-2hvr-qmmx-gw49, MINI-2m8h-5j2f-vvfh, MINI-2pxw-cmrp-5g4m, MINI-36mx-mr33-3qw2, MINI-3ff5-wc7c-635p, MINI-3jfm-hhp7-3fv9, MINI-42qg-ww8j-wj73, MINI-43xv-4j9v-p466, MINI-44xc-xqxm-q3vf, MINI-462c-fj27-553w, MINI-47mw-wg93-fcx8, MINI-4c9v-xc7c-mvx3, MINI-4gf2-w2f8-x34q, MINI-4jwp-w6j8-hr76, MINI-4p3v-492h-4hv9, MINI-4rpv-86wr-qf4h, MINI-54qp-57jc-j7jp, MINI-57c5-rrqq-xfhv, MINI-5cwp-xxrm-6r62, MINI-5hhc-m6rm-88p2, MINI-5j25-7994-hg8c, MINI-5rrf-hhjx-q2gf, MINI-5vh9-fc6f-v229, MINI-5vjw-v888-87wj, MINI-5wrm-w97r-f7vj, MINI-64ww-mhgp-3mc2, MINI-692q-f84q-p3h3, MINI-6x7w-vr2f-6mfg, MINI-742x-wxcq-vmv7, MINI-75g8-vr74-9wh7, MINI-76fq-632p-fx4x, MINI-7g99-2hvp-cm4r, MINI-7gwg-pp66-3vx8, MINI-7qc5-rgq5-9534, MINI-7rvx-8mr4-3vcc, MINI-7w4x-f6qv-wpm9, MINI-8c78-7m57-j7hx, MINI-8cfv-v7cw-x239, MINI-8cg4-2jv2-rwp5, MINI-8cwc-7r92-xf2h, MINI-8g46-5j8m-4jg4, MINI-8g6x-v5vq-rfw7, MINI-8jvc-gqpj-qgwq, MINI-8xp2-qwxf-3g4j, MINI-8xvv-4r6r-9ww2, MINI-98r7-g73v-fj66, MINI-98wx-4hpm-q2gg, MINI-9gmx-fg44-2rxc, MINI-9jmh-cvg5-9hw7, MINI-9p52-79x8-h26f, MINI-9q9r-7qjq-qw87, MINI-9qpj-64jr-8vgx, MINI-9rvg-8vh4-v3qc, MINI-9v6j-5w4q-6cxf, MINI-9xm2-7mgg-3g6g, MINI-c3gp-4xqq-q22m, MINI-cq9m-c5pp-q6cf, MINI-cx37-2mj6-jprf, MINI-f2vh-wg2p-j52r, MINI-f5h2-pjwx-2pch, MINI-f884-73hx-p88x, MINI-f9vg-h52j-j385, MINI-fr9x-9c2v-g6g2, MINI-fxv5-f9qr-jcpr, MINI-g6p8-8f9v-mph9, MINI-g7f3-m6x8-97fg, MINI-g9hj-42r5-wmxp, MINI-gcf9-pq8h-rw8w, MINI-gg4c-x674-pvrw, MINI-gvqj-wqh8-hfcm, MINI-gxqc-jpcg-x2q3, MINI-h3cx-g8v7-x6fx, MINI-h423-52gh-j95g, MINI-h759-jrm7-j5h4, MINI-hcqc-wgfv-4pj9, MINI-hjx3-6mhm-mrwq, MINI-hx8w-rc38-2xfm, MINI-jg46-qrqw-j3m6, MINI-jg4v-qw7m-9j44, MINI-jr9g-wcxw-g4jh, MINI-jv4p-grjq-hw4q, MINI-m23g-6c53-xfww, MINI-m55r-r77p-788p, MINI-m56r-fpgr-c46p, MINI-m5p7-q7hx-x788, MINI-m89p-4785-vc8h, MINI-mc35-77mx-hcfx, MINI-mgrj-77f2-6gj2, MINI-mmxc-6h58-4cvp, MINI-mp8j-9v7j-gvqv, MINI-mphj-9w6c-rrw3, MINI-mppf-3q74-8c44, MINI-mv5c-vrpm-9936, MINI-mvwq-8cf3-2xrj, MINI-p6j5-ffmm-mprv, MINI-p7ww-q7cq-ppm4, MINI-pfgh-p926-jxff, MINI-pg8g-4mhh-vf73, MINI-pgv7-p92h-2832, MINI-pgvm-3j55-7r49, MINI-pj3h-936q-jxx2, MINI-pqp2-vrwr-wf5p, MINI-prxq-7qjp-v7v9, MINI-pw28-hrqq-jj4h, MINI-q9r6-9c58-f76m, MINI-qc94-vf46-8hc7, MINI-qg5j-h9gf-3v7j, MINI-qqj2-xfrm-5hg5, MINI-qr3q-ccwh-8fc3, MINI-qv92-p7v2-p2m8, MINI-qxr3-fmvf-w2xp, MINI-r4f2-2j63-gg3q, MINI-r4vf-j2x6-r989, MINI-r8mp-79p8-x4p7, MINI-rgqr-vrqf-qh7x, MINI-rpr3-cv3m-jfc9, MINI-rwpw-mcx9-3c3h, MINI-rx2j-cfq9-9p4h, MINI-v265-g92h-4p2w, MINI-v5h4-ghmw-qjh4, MINI-v689-w233-cxp7, MINI-vcrm-rm7v-fcfm, MINI-vfg3-wp7g-jwf6, MINI-vjpj-xg8w-xvmp, MINI-vv6g-684j-xcxp, MINI-vwq7-x7cj-xf98, MINI-vxcr-gxxf-3rgc, MINI-w388-mghp-4h7x, MINI-w6r7-q3w9-22w2, MINI-w7rj-mh5w-g3m2, MINI-w96w-jx3h-8p87, MINI-wm4h-m86m-5w5r, MINI-wq86-6xwc-vg49, MINI-wrvh-fhrm-h44v, MINI-x34q-mj84-fc84, MINI-x4ph-jqjq-5rm7, MINI-x677-gx83-4p88, MINI-x69q-vfc4-mcm8, MINI-x6fm-gv29-pqg6, MINI-x76m-cj2v-279r, MINI-x7m8-gqcg-3x73, MINI-xcwf-r87g-jf2p, MINI-xmqx-7q53-xv3h, MINI-xqwc-qcjq-rw6x, MINI-xr77-xm9v-2928, ROOT-APP-GOBINARY-CVE-2026-42154, UBUNTU-CVE-2026-42154 ## What is CVE-2026-42154? CVE-2026-42154 is a high-severity denial of service vulnerability in prometheus, published on 4 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description 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. Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling), CWE-789 (Memory Allocation with Excessive Size Value), CWE-400 (Uncontrolled Resource Consumption) ## Which versions are affected by CVE-2026-42154? 9 open source packages ship an affected version, including github.com/prometheus/prometheus, prometheus and github.com/prometheus/prometheus/v2. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `github.com/prometheus/prometheus` | Go | All versions | 0.305.2, 0.311.3 | | `github.com/prometheus/prometheus` | Go | All versions | 0.305.2 | | `github.com/prometheus/prometheus` | Go | All versions | 0.305.2 | | `github.com/prometheus/prometheus` | Go | From 0.306.0 | 0.311.3 | | `github.com/prometheus/prometheus` | Go | From 0.306.0 | 0.311.3 | | `github.com/prometheus/prometheus` | Go | From 1.0.0-rc.0 to 2.5.0 | None | | `github.com/prometheus/prometheus` | Go | From 1.0.0-rc.0 to 2.5.0 | None | | `prometheus` | Bitnami | All versions | 0.305.3, 0.311.3, 3.5.3, 3.11.3 | | `github.com/prometheus/prometheus/v2` | Go | All versions | None | Products: Prometheus Prometheus. ## How do I fix CVE-2026-42154? Upgrade github.com/prometheus/prometheus to a fixed version for your release line: 0.305.2 or 0.311.3. ## Is CVE-2026-42154 being exploited? There is no known exploitation of CVE-2026-42154 in the wild and no public exploit code. Public exploit code: - # CVE-2026-42154 — Prometheus Remote Read Snappy DoS (github_poc): https://github.com/ShadowByte1/CVE-2026-42154 ## Other vulnerabilities in prometheus - [CVE-2026-42151](https://insights.sbomify.com/CVE-2026-42151/): Prometheus Azure AD remote write OAuth client secret exposed via config API (high 7.5) - [CVE-2021-29622](https://insights.sbomify.com/CVE-2021-29622/): Arbitrary redirects under /new endpoint (medium 6.5) - [CVE-2019-3826](https://insights.sbomify.com/CVE-2019-3826/): Cross-site scripting in prometheus (medium 6.1) - [CVE-2026-40179](https://insights.sbomify.com/CVE-2026-40179/): Prometheus: Stored XSS via metric names and label values in web UI tooltips and metrics explorer (medium 5.3) - [CVE-2026-44903](https://insights.sbomify.com/CVE-2026-44903/): Prometheus: Stored XSS via crafted histogram bucket label values in the heatmap display of the old Prometheus web UI (medium 5.1) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-42154 and fix it if it is affected. What it is: CVE-2026-42154 is a high-severity denial of service vulnerability in prometheus, published on 4 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2026-42154 in the wild and no public exploit code. Affected packages and fixed versions: - github.com/prometheus/prometheus (Go): affected all versions; fixed in 0.305.2, 0.311.3 - github.com/prometheus/prometheus (Go): affected all versions; fixed in 0.305.2 - github.com/prometheus/prometheus (Go): affected all versions; fixed in 0.305.2 - github.com/prometheus/prometheus (Go): affected from 0.306.0; fixed in 0.311.3 - github.com/prometheus/prometheus (Go): affected from 0.306.0; fixed in 0.311.3 - github.com/prometheus/prometheus (Go): affected from 1.0.0-rc.0 up to 2.5.0; no fix listed - github.com/prometheus/prometheus (Go): affected from 1.0.0-rc.0 up to 2.5.0; no fix listed - prometheus (Bitnami): affected all versions; fixed in 0.305.3, 0.311.3, 3.5.3, 3.11.3 - github.com/prometheus/prometheus/v2 (Go): affected all versions; no fix listed Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-42154/ (Markdown: https://insights.sbomify.com/CVE-2026-42154/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-42154 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-42154 - OSV: https://osv.dev/vulnerability/CVE-2026-42154 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-42154/ Summaries are generated and may contain mistakes; the official description above is the record.