GHSA-87m9-rv8p-rgmg is a high-severity (CVSS 7.5) vulnerability in github.com/mostynb/go-grpc-compression. A fix is available for github.com/mostynb/go-grpc-compression — see the affected versions and patch details below.
go-grpc-compression has a zstd decompression bombing vulnerability
Real-World Exposure
github.com/mostynb/go-grpc-compressionReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Impact
A malicious user could cause a denial of service (DoS) when using a specially crafted gRPC request. The decompression mechanism for zstd did not respect the limits imposed by gRPC, allowing rapid memory usage increases.
Versions v1.1.4 through to v1.2.2 made use of the Decoder.DecodeAll function in github.com/klauspost/compress/zstd to decompress data provided by the peer. The vulnerability is exploitable only by attackers who can send gRPC payloads to users of github.com/mostynb/go-grpc-compression/zstd or github.com/mostynb/go-grpc-compression/nonclobbering/zstd.
Patches
Version v1.2.3 of github.com/mostynb/go-grpc-compression avoids the issue by not using the Decoder.DecodeAll function in github.com/klauspost/compress/zstd.
All users of github.com/mostynb/go-grpc-compression/zstd or github.com/mostynb/go-grpc-compression/nonclobbering/zstd in the affected versions should update to v1.2.3.
Workarounds
Other compression formats were not affected, users may consider switching from zstd to another format without upgrading to a newer release.
References
This issue was uncovered during a security audit performed by Miroslav Stampar of 7ASecurity, facilitated by OSTIF, for the OpenTelemetry project.
https://opentelemetry.io/blog/2024/cve-2024-36129 https://github.com/open-telemetry/opentelemetry-collector/security/advisories/GHSA-c74f-6mfw-mm4v
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/mostynb/go-grpc-compression | ≥ 1.1.4&&< 1.2.3 | 1.2.3go get github.com/mostynb/go-grpc-compression@v1.2.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/mostynb/go-grpc-compression, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/mostynb/go-grpc-compression to 1.2.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-87m9-rv8p-rgmg is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-87m9-rv8p-rgmg can be triaged on real exposure rather than presence alone.
Tailored to GHSA-87m9-rv8p-rgmg. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-87m9-rv8p-rgmg in your dependencies?
O3 Security finds GHSA-87m9-rv8p-rgmg across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.