{"id":"AZL-80975","summary":"CVE-2026-33936 affecting package python-ecdsa for versions less than 0.19.2-1","details":"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 available buffer. For example, an OCTET STRING that declares a length of 4096 bytes but provides only 3 bytes is parsed successfully instead of being rejected. Because of that, a crafted DER input can cause `SigningKey.from_der()` to raise an internal exception (`IndexError: index out of bounds on dimension 1`) rather than cleanly rejecting malformed DER (e.g., raising `UnexpectedDER` or `ValueError`). Applications that parse untrusted DER private keys may crash if they do not handle unexpected exceptions, resulting in a denial of service. Version 0.19.2 patches the issue.","modified":"2026-08-28T17:47:34.156820242Z","published":"2026-03-27T23:17:13Z","upstream":["CVE-2026-33936"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33936"}],"affected":[{"package":{"name":"python-ecdsa","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/python-ecdsa"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.19.2-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-80975.json"}}],"schema_version":"1.9.0"}