CVE-2020-14967 RSA PKCS#1 decryption vulnerability with prepending zeros in jsrsasign
An attacker can trigger memory corruption in the jsrsasign library by prepending null bytes to RSA ciphertexts, potentially leading to code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2020-14967?
CVE-2020-14967 is a critical memory corruption vulnerability in n/a, published on 22 Jun 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An issue was discovered in the jsrsasign package before 8.0.18 for Node.js. Its RSA PKCS1 v1.5 decryption implementation does not detect ciphertext modification by prepending '\0' bytes to ciphertexts (it decrypts modified ciphertexts without error). An attacker might prepend these bytes with the goal of triggering memory corruption issues.
Weakness: CWE-119
Which versions are affected by CVE-2020-14967?
2 open source packages ship an affected version, including jsrsasign. It affects 2 products.
| Package | Affected | Fixed in |
|---|---|---|
jsrsasign npm | All versions | 8.0.18 |
jsrsasign npm | All versions | 8.0.18 |
Products include Kjur Jsrsasign, Netapp Max Data.
How do I fix CVE-2020-14967?
Upgrade jsrsasign to 8.0.18 or later.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2020-14967 being exploited?
There is no known exploitation of CVE-2020-14967 in the wild and no public exploit code.
Other vulnerabilities in n/a
- CVE-2020-14968 RSA-PSS signature validation vulnerability by prepending zeros in jsrsasign
- CVE-2026-4601 jsrsasign: Missing cryptographic validation during DSA signing enables private key extraction
- CVE-2026-4599 jsrsasign: Incomplete Comparison Allows DSA Private Key Recovery via Biased Nonce Generation
- CVE-2026-4600 jsrsasign: DSA signatures or X.509 certificates can be forged via DSA domain-parameter validation in KJUR.crypto.DSA.setPublic
- CVE-2021-30246 RSA signature validation vulnerability on maleable encoded message in jsrsasign
Sources
Also known as GHSA-xxxq-chmp-67g4.