How severe is CVE-2026-33894?

CVE-2026-33894 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2026-33894?

CVE-2026-33894 affects the following packages: node-forge (npm). Ecosystems affected: npm.

How do I fix CVE-2026-33894?

Update node-forge to 1.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33894 is resolved across your whole dependency graph.

How do I detect CVE-2026-33894 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for node-forge. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2026-33894 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2026-33894?

O3 pinpoints whether CVE-2026-33894 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2026-33894 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-33894 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What type of vulnerability is CVE-2026-33894?

CVE-2026-33894 is classified as Improper Input Validation (CWE-20), CWE-347 (CWE-347). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-33894 published, and has it been updated?

CVE-2026-33894 was published on March 27, 2026 and was last updated on August 4, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

CVE-2026-33894

HIGH

CVE-2026-33894 is a high-severity (CVSS 7.5) Improper Input Validation vulnerability in node-forge. O3 Security confirms whether CVE-2026-33894 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Forge has signature forgery in RSA-PKCS due to ASN.1 extra field

Also known asGHSA-ppp5-5v6c-4jwp

Published

Mar 27, 2026

Updated

Aug 4, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Blast Radius

1 pkg affected

Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.

node-forgenpm

36.9Mdownloads / week

Description

Forge (also called node-forge) is a native implementation of Transport Layer Security in JavaScript. Prior to version 1.4.0, RSASSA PKCS#1 v1.5 signature verification accepts forged signatures for low public exponent keys (e=3). Attackers can forge signatures by stuffing “garbage” bytes within the ASN structure in order to construct a signature that passes verification, enabling Bleichenbacher style forgery. This issue is similar to CVE-2022-24771, but adds bytes in an addition field within the ASN structure, rather than outside of it. Additionally, forge does not validate that signatures include a minimum of 8 bytes of padding as defined by the specification, providing attackers additional space to construct Bleichenbacher forgeries. Version 1.4.0 patches the issue.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`node-forge`	all versions	1.4.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for node-forge. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update node-forge to 1.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33894 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 pinpoints whether CVE-2026-33894 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2026-33894. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Forge (also called `node-forge`) is a native implementation of Transport Layer Security in JavaScript. Prior to version 1.4.0, RSASSA PKCS#1 v1.5 signature verification accepts forged signatures for low public exponent keys (e=3). Attackers can forge signatures by stuffing “garbage” bytes within the ASN structure in order to construct a signature that passes verification, enabling Bleichenbacher style forgery. This issue is similar to CVE-2022-24771, but adds bytes in an addition field within the ASN structure, rather than outside of it. Additionally, forge does not validate that signatures i

O3 Security · Impact-Aware SCA

Is CVE-2026-33894 in your dependencies?

O3 detects CVE-2026-33894 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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