Out-of-Bounds Read in mesop (CVE-2026-34824)
Summary
Vulnerability in mesop (CVE-2026-34824). Risk of unauthorized operations or information disclosure. Exploitable via handle_websocket. Mitigation: upgrade to 1.2.5 or later.
Original description
The description as published by the source.
Mesop is a Python-based UI framework that allows users to build web applications. From version 1.2.3 to before version 1.2.5, an uncontrolled resource consumption vulnerability exists in the WebSocket implementation of the Mesop framework. An unauthenticated attacker can send a rapid succession of WebSocket messages, forcing the server to spawn an unbounded number of operating system threads. This leads to thread exhaustion and Out of Memory (OOM) errors, causing a complete Denial of Service (DoS) for any application built on the framework. This issue has been patched in version 1.2.5.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-34824 has been found in mesop.
Attackers can target a specific entry point like handle_websocket over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: upgrade mesop to 1.2.5 or later.
If unsure, ask your IT team or search "mesop CVE-2026-34824" on the vendor's site.
CVE-2026-34824 (mesop) — CWE-125 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: handle_websocket / threading.Thread / ui_request / exploit_dos.py
Patched: 1.2.5 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Out-of-bounds read (CWE-125) exists in mesop. Attackers reach the vulnerable code path via handle_websocket without authentication.
Check the vendor advisory for the affected versions of mesop. Attack surface: handle_websocket / threading.Thread / ui_request / exploit_dos.py.
Severity: High (CVSS 7.5/10). Risk of unauthorized operations or information disclosure.
Update to 1.2.5.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'mesop' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'mesop' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
mesopを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade mesop to 1.2.5ステージング環境で 1.2.5 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- patch github.com
- web github.com