CVE-2026-33936Improper Input Validation in Python-ecdsa

Severity
5.3MEDIUMNVD
EPSS
0.1%
top 71.13%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedMar 27

Description

The `ecdsa` PyPI package is a pure Python implementation of ECC (Elliptic Curve Cryptography) with support for ECDSA (Elliptic Curve Digital Signature Algorithm), EdDSA (Edwards-curve Digital Signature Algorithm) and ECDH (Elliptic Curve Diffie-Hellman). Prior to version 0.19.2, an issue in the low-level DER parsing functions can cause unexpected exceptions to be raised from the public API functions. `ecdsa.der.remove_octet_string()` accepts truncated DER where the encoded length exceeds the ava

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LExploitability: 3.9 | Impact: 1.4

Affected Packages4 packages

CVEListV5tlsfuzzer/python-ecdsa< 0.19.2
NVDtlsfuzzer/ecdsa< 0.19.2
PyPItlsfuzzer/ecdsa< 0.19.2

Patches

🔴Vulnerability Details

4
GHSA
python-ecdsa: Denial of Service via improper DER length validation in crafted private keys2026-03-27
CVEList
python-ecdsa: Denial of Service via improper DER length validation in crafted private keys2026-03-27
OSV
CVE-2026-33936: The `ecdsa` PyPI package is a pure Python implementation of ECC (Elliptic Curve Cryptography) with support for ECDSA (Elliptic Curve Digital Signature2026-03-27
OSV
python-ecdsa: Denial of Service via improper DER length validation in crafted private keys2026-03-27

📋Vendor Advisories

3
Red Hat
python-ecdsa: ecdsa: Denial of Service via crafted DER input2026-03-27
Microsoft
python-ecdsa: Denial of Service via improper DER length validation in crafted private keys2026-03-10
Debian
CVE-2026-33936: python-ecdsa - The `ecdsa` PyPI package is a pure Python implementation of ECC (Elliptic Curve ...2026

🕵️Threat Intelligence

1
Wiz
CVE-2026-33936 Impact, Exploitability, and Mitigation Steps | Wiz
CVE-2026-33936 — Improper Input Validation | cvebase