CVE-2025-66030: Digitalbazaar Forge Auth Bypass Flaw

CVE-2025-66030 Overview

CVE-2025-66030 is an integer overflow vulnerability in node-forge, a native JavaScript implementation of Transport Layer Security (TLS). Versions 1.3.1 and below fail to bounds-check individual arc values when encoding Object Identifiers (OIDs) inside ASN.1 structures. Remote, unauthenticated attackers can craft ASN.1 payloads containing oversized OID arcs that get truncated by 32-bit bitwise operations. The truncated arcs may then collide with smaller, trusted OIDs, bypassing downstream OID-based security decisions. Digital Bazaar patched the issue in node-forge version 1.3.2.

Critical Impact
Attackers can forge ASN.1 OIDs that decode to trusted identifiers, undermining OID-based trust checks in TLS, certificate, and PKCS parsing paths that depend on node-forge.

Affected Products

Digital Bazaar node-forge versions ≤ 1.3.1 (Node.js package)
Applications embedding node-forge for ASN.1, X.509, or PKCS parsing
Downstream libraries and services that make trust decisions based on OID values parsed by node-forge

Discovery Timeline

2025-11-26 - CVE-2025-66030 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-66030

Vulnerability Analysis

The vulnerability is classified as an Integer Overflow ([CWE-190]) in the ASN.1 OID encoding routine of lib/asn1.js. OIDs are represented as sequences of unsigned integer arcs. node-forge parsed each arc using parseInt, then applied 32-bit bitwise operations (& 0x7F and >>> 7) to encode the value into base-128 bytes. JavaScript bitwise operators coerce operands to signed 32-bit integers, silently truncating any value above 0xFFFFFFFF. An attacker who supplies an oversized arc can therefore produce an encoded OID whose bytes match a smaller, trusted OID after the modular reduction.

Root Cause

The root cause is the absence of a bounds check on individual OID arc values before they enter 32-bit bitwise encoding. Because node-forge never validated that value <= 0xFFFFFFFF, oversized arcs were reduced modulo 2³² instead of being rejected. Applications that later compared the parsed OID string against an allow-list (for example, certificate policy OIDs, extended key usage OIDs, or algorithm identifiers) received an unexpected, attacker-chosen value.

Attack Vector

The attack vector is network-based and requires no authentication. An attacker delivers a crafted ASN.1 blob, such as an X.509 certificate, PKCS#7 message, or CSR, containing an OID with one or more oversized arcs. When node-forge decodes the structure, the truncated OID may match a security-relevant identifier that the application trusts. Exploitation complexity is elevated because the attacker must find an oversized arc whose 32-bit truncation matches a target trusted OID.

javascript

// Patch in lib/asn1.js - Fix "ASN.1 OID Integer Truncation" advisory
last = true;
valueBytes = [];
value = parseInt(values[i], 10);
// TODO: Change bitwise logic to allow larger values.
if(value > 0xffffffff) {
  throw new Error('OID value too large; max is 32-bits.');
}
do {
  b = value & 0x7F;
  value = value >>> 7;

Source: digitalbazaar/forge commit 3e0c35a

Detection Methods for CVE-2025-66030

Indicators of Compromise

ASN.1 payloads containing OID arcs with numeric values greater than 0xFFFFFFFF (4,294,967,295).
Certificates, CSRs, or PKCS#7 messages where a parsed OID resolves to a trusted policy or algorithm identifier despite encoding anomalies.
Application logs showing successful trust decisions on inputs that also produce ASN.1 parsing warnings.

Detection Strategies

Inventory Node.js applications using Software Composition Analysis (SCA) to locate all direct and transitive dependencies on node-forge at version ≤ 1.3.1.
Instrument ASN.1 parsing paths to log raw OID byte sequences alongside the decoded string, then alert on arcs exceeding 32-bit range.
Add integration tests that feed known oversized-arc test vectors through certificate validation code paths.

Monitoring Recommendations

Monitor package registries and build pipelines for continued use of node-forge versions ≤ 1.3.1.
Alert on ingestion of X.509 or PKCS objects that contain unusually long OID arc encodings.
Track certificate policy and extended key usage OID decisions and correlate against source certificate hashes for anomaly review.

How to Mitigate CVE-2025-66030

Immediate Actions Required

Upgrade node-forge to version 1.3.2 or later across all applications, container images, and serverless functions.
Rebuild and redeploy any artifact that bundles node-forge, including web frontends where the library ships to browsers.
Review OID allow-lists and confirm that OID-based trust decisions include additional cryptographic checks, not just string comparison.

Patch Information

The fix is committed in digitalbazaar/forge commit 3e0c35a and released in node-forge 1.3.2. It adds an explicit check that throws OID value too large; max is 32-bits. when any arc exceeds 0xFFFFFFFF. Full advisory details are available in GitHub Security Advisory GHSA-65ch-62r8-g69g.

Workarounds

Validate untrusted ASN.1 input at the application layer and reject OID arcs greater than 0xFFFFFFFF before invoking node-forge.
Where feasible, replace node-forge OID parsing with a maintained ASN.1 library that rejects out-of-range arcs.
Constrain trust decisions to a minimal OID allow-list and pair OID checks with certificate chain, algorithm, and key usage validation.

bash

# Upgrade node-forge to the patched release
npm install node-forge@^1.3.2
npm ls node-forge          # confirm no transitive < 1.3.2 remains
npm audit --production     # verify advisory GHSA-65ch-62r8-g69g is resolved