---
title: "CVE-2026-48853: gRPC Erlang package vulnerable to Remote Code Execution with attacker-controlled gRPC payloads"
url: https://erroneo.us/security/cve/CVE-2026-48853/
description: "CVE-2026-48853 (grpc (Hex (Erlang/Elixir))): Deserialization of Untrusted Data and Allocation of Resources Without Limits or Throttling vulnerabilities in…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-06-15
date_modified: 2026-09-24
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-48853"
kev: false
cvss: 9.2
epss: 0.00784
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-48853: gRPC Erlang package vulnerable to Remote Code Execution with attacker-controlled gRPC payloads

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.8% , percentile 56: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 56% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes grpc (Hex (Erlang/Elixir)) >= 0.4.0, < 1.0.0, fixed in 1.0.0 . Check your lockfile, including transitive dependencies.

## What it is

Deserialization of Untrusted Data and Allocation of Resources Without Limits or Throttling vulnerabilities in elixir-grpc grpc allow unauthenticated attackers to crash the BEAM node via atom table exhaustion and, when a decoded term flows into a call site that invokes it, achieve remote code execution on the server. 'Elixir.GRPC.Codec.Erlpack':decode/2 (lib/grpc/codec/erlpack.ex) calls :erlang.binarytoterm/1 on the raw gRPC message body without the :safe option, no size bound, and no type guard. Any unauthenticated peer that sends a request with Content-Type: application/grpc+erlpack can send a crafted payload that mints arbitrary new atoms (which are never garbage-collected, exhausting the bounded atom table and crashing the VM) or that encodes a fun term which, if applied anywhere downstream, executes attacker-controlled code inside the server process. This issue affects grpc: from 0.4.0 before 1.0.0.

## Affected packages

- Hex (Erlang/Elixir) `grpc` >= 0.4.0, < 1.0.0 → fixed: 1.0.0

## Affected products (CVE record)

- elixir-grpc grpc: 0.4.0 < 1.0.0
- elixir-grpc grpc: 25bcc569fe2cc4478531a6c546c923205fc751c9 < 272a97a5ea1b46af1819f14a831fcf35fc91f992

## Severity

- EEF CVSS 4.0: 9.2 `CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`
- GitHub CVSS 4.0: 9.2 `CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.78% probability of exploitation activity in the next 30 days; percentile 56.

## Sources

- [github.com](https://github.com/elixir-grpc/grpc/security/advisories/GHSA-grp7-v8xh-rj7h)
- [Fix commit 272a97a in elixir-grpc/grpc](https://github.com/elixir-grpc/grpc/commit/272a97a5ea1b46af1819f14a831fcf35fc91f992)
- [GitHub Advisory GHSA-grp7-v8xh-rj7h](https://github.com/advisories/GHSA-grp7-v8xh-rj7h)
- [CVE.org record CVE-2026-48853](https://www.cve.org/CVERecord?id=CVE-2026-48853)
- [NVD entry CVE-2026-48853](https://nvd.nist.gov/vuln/detail/CVE-2026-48853)
- [EEF CNA record for CVE-2026-48853](https://cna.erlef.org/cves/CVE-2026-48853.html)
- [OSV record EEF-CVE-2026-48853](https://osv.dev/vulnerability/EEF-CVE-2026-48853)
- [Introducing commit 25bcc56 in elixir-grpc/grpc](https://github.com/elixir-grpc/grpc/commit/25bcc569fe2cc4478531a6c546c923205fc751c9)
- [github.com](https://github.com/elixir-grpc/grpc/pull/540)
- [github.com](https://github.com/elixir-grpc/grpc/releases/tag/v1.0.0)

---
Source page: https://erroneo.us/security/cve/CVE-2026-48853/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt