Vulnerability in grpc (CVE-2026-53430)
Summary
Vulnerability in grpc (CVE-2026-53430). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 1.0.0 or later.
Original description
The description as published by the source.
Summary
An unauthenticated remote peer can crash any gRPC server built on this library by sending a small gzip-compressed frame that decompresses to gigabytes, exhausting the BEAM node's heap and triggering an OOM kill (denial of service).
Introduced in https://github.com/elixir-grpc/grpc/commit/beae6800fc8baf126f3fe7107d86a50e105275ba
Details
GRPC.Compressor.Gzip.decompress/1 (lib/grpc/compressor/gzip.ex:12-14) calls :zlib.gunzip/1 directly on attacker-controlled bytes with no size limit, no ratio check, and no incremental decoding. Because this module is registered as a GRPC.Compressor implementation, it is invoked automatically whenever an incoming gRPC frame carries grpc-encoding: gzip. :zlib.gunzip/1 allocates the entire decompressed result as a single binary before returning, so a highly compressible payload (e.g. a few kilobytes of zeros, which gzip compresses at roughly 1000:1) expands to multiple gigabytes inside a single function call. The server's max_receive_message_length is enforced only against the already-decompressed message, so it provides no protection here. A single request is sufficient to OOM-kill the node.
PoC
A script that verifies the vulnerability is attached to the end of this report. Run it against a stock gRPC server using this library; the BEAM node's memory usage will balloon and the VM will be OOM-killed after a single request.
Impact
This is a decompression bomb / denial-of-service vulnerability. Any service tha…
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-2026-53430 has been found in grpc.
Risk of unauthorized operations or information disclosure.
What to do: upgrade grpc to 1.0.0 or later.
If unsure, ask your IT team or search "grpc CVE-2026-53430" on the vendor's site.
CVE-2026-53430 (grpc) — CWE-409
Patched: 1.0.0 — 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.
A vulnerability (CWE-409) exists in grpc.
Check the vendor advisory for the affected versions of grpc.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 1.0.0.
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 'grpc' . 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 'grpc' . | 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
grpc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 grpc to 1.0.0ステージング環境で 1.0.0 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。
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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 nvd.nist.gov
- package hex.pm
- package github.com
- web cna.erlef.org
- web github.com
- web github.com
- web osv.dev
- web github.com
- web github.com
- web github.com