CVSS 4.0
8.2 highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCVE-2026-121808 Memory exhaustion via compressed Erlang terms in the elixir-grpc Erlpack codec
High (8.2) in elixir-grpc. Fixed in grpc 1.0.0.
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Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in elixir-grpc grpc_core and grpc allows unauthenticated attackers to exhaust server memory via a compressed Erlang external term in a gRPC message body.
GRPC.Codec.Erlpack.decode/2 (grpc_core/lib/grpc/codec/erlpack.ex, and lib/grpc/codec/erlpack.ex before the package split) passes the message body to :erlang.binary_to_term/2. That function inflates a compressed term in full before it returns. The codec sets no limit on the decoded size, and its type checks run only on the decoded term. The server's max_body_size limit counts the compressed bytes of the request. A request with Content-Type: application/grpc+erlpack can therefore make the server allocate a term much larger than the request body.
This issue affects grpc: from 0.4.0 before 1.0.0; grpc_core: from 1.0.0 before 1.1.0.
Severity
- CWE
- CWE-409 Improper Handling of Highly Compressed Data (Data Amplification)
- Published
- Assigned by
- EEF (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| elixir-grpc grpc | from 0.4.0 before 1.0.0 |
| elixir-grpc grpc_core | from 1.0.0 before 1.1.0 |
Fix and patched versions
grpc(Hex): fixed in 1.0.0grpc_core(Hex): fixed in 1.1.0
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| EEF-CVE-2026-121808 | Hex | grpc | >=0.4.0 <1.0.0 | 1.0.0 |
| EEF-CVE-2026-121808 | Hex | grpc_core | >=1.0.0 <1.1.0 | 1.1.0 |
| EEF-CVE-2026-121808 | no fix published | |||
| EEF-CVE-2026-121808 | v1.0.6, v1.0.3, v1.0.0 | no fix published |
References
- https://cna.erlef.org/cves/CVE-2026-121808.html
- https://github.com/elixir-grpc/grpc/commit/0332faae5f5e132314794dbfdae5edecbccea292
- https://github.com/elixir-grpc/grpc/commit/25bcc569fe2cc4478531a6c546c923205fc751c9
- https://github.com/elixir-grpc/grpc/commit/d6bc56ac75dfb6c02db2099909210a37c9be8db6
- https://github.com/elixir-grpc/grpc/security/advisories/GHSA-xxp9-7hp4-rqwp
- https://osv.dev/vulnerability/EEF-CVE-2026-121808