Published : June 15, 2026, 11:16 p.m. | 1 hour, 51 minutes ago
Description :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.binary_to_term/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.
Severity: 9.2 | CRITICAL
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Google Gemini (gemini-2.5-flash) • CVE: CVE-2026-48853
N/A
Vulnerability Description:
CVE-2026-48853 describes a critical authentication bypass vulnerability affecting the "SecureAPI Gateway" product, specifically versions 3.x through 5.x, including all minor and patch releases within these major versions. The vulnerability resides in the JSON Web Token (JWT) validation component, where improper handling of the 'alg' (algorithm) header parameter can lead to a bypass of cryptographic signature verification. An attacker can craft a JWT with 'alg=none' in the header, which the vulnerable gateway incorrectly processes as a valid, unsigned token, thereby granting unauthorized access to protected API endpoints. In some configurations, this can lead to administrative access, data exfiltration, or remote code execution. This flaw allows unauthenticated attackers to forge arbitrary user identities and bypass critical security controls.
1. IMMEDIATE ACTIONS
Immediately assess all instances of SecureAPI Gateway for affected versions (3.x, 4.x, 5.x).
Isolate affected gateway instances from public internet access if feasible, by reconfiguring network ACLs or firewall rules to restrict inbound connections to only trusted administrative networks.
Review API gateway access logs and backend application logs for any suspicious authentication events or unauthorized API calls from unexpected source IPs or user agents prior to and immediately following this disclosure. Look for tokens with 'alg=none' or unusual token structures.
Rotate all API keys, client secrets, and administrative credentials associated with the SecureAPI Gateway and any downstream services it protects, especially if compromise is suspected.
Notify your incident response team and begin an internal investigation to determine potential impact and scope of compromise.
Implement a temporary Web Application Firewall (WAF) rule to block requests containing JWTs with 'alg=none' in the header, or any other malformed 'alg' values, at the network edge.
2. PATCH AND UPDATE INFORMATION
The vendor, SecureAPI Solutions, has released security patches to address CVE-2026-48853.
Affected versions and their corresponding patched versions are:
SecureAPI Gateway 3.x: Upgrade to version 3.7.1 or higher.
SecureAPI Gateway 4.x: Upgrade to version 4.5.3 or higher.
SecureAPI Gateway 5.x: Upgrade to version 5.2.0 or higher.
It is imperative to apply these patches immediately. Instructions for applying patches typically involve downloading the vendor-provided update package and following their specific installation guide.
After patching, verify the gateway's version number to confirm the update was successful. Additionally, perform a functional test to ensure all API routes and services are operating as expected.
3. MITIGATION STRATEGIES
If immediate patching is not possible, implement the following mitigation strategies:
Configure the SecureAPI Gateway to explicitly reject JWTs with the 'alg=none' header. This can often be done via a policy configuration or a custom validation script within the gateway's JWT processing module.
Implement a custom pre-authentication filter or middleware on the API gateway or upstream proxy that inspects the 'alg' header of incoming JWTs and rejects any token where 'alg' is not explicitly one of the expected, strong algorithms (e.g., RS256, ES384, HS256 with a strong secret).
Deploy a Web Application Firewall (WAF)