CVE catalog
CVE-2026-33936
The `ecdsa` PyPI package is a pure Python…
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.
- Severity
- Medium · CVSS 5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.48% · Oct 27, 2026
Projects and upstream resources
Reported versions and fixes
Each observation applies to its named package, distribution, and release. Distribution backports can fix a vulnerability while retaining an older upstream version number.
Version impact has not been established. The original provider fields are retained below.
Provider details and historical evidence
Original provider fields
{
"package_releases": [
{
"name": "python-ecdsa",
"status": "fixed",
"release": "sid",
"version": "0.19.2-2"
},
{
"name": "python-ecdsa",
"status": "fixed",
"release": "forky",
"version": "0.19.2-2"
},
{
"name": "python-ecdsa",
"status": "fixed",
"release": "trixie",
"version": "0.19.1-1+deb13u1"
},
{
"name": "python-ecdsa",
"status": "vulnerable",
"release": "bookworm",
"version": "0.18.0-3"
}
],
"fixed_versions": [
{
"bug": 1132164,
"name": "python-ecdsa",
"type": "source",
"origin": null,
"release": "sid",
"urgency": "not yet assigned",
"fixed_version": "0.19.2-1"
},
{
"bug": 1132164,
"name": "python-ecdsa",
"type": "source",
"origin": null,
"release": "forky",
"urgency": "not yet assigned",
"fixed_version": "0.19.2-1"
},
{
"bug": 1132164,
"name": "python-ecdsa",
"type": "source",
"origin": null,
"release": "trixie",
"urgency": "not yet assigned",
"fixed_version": "0.19.1-1+deb13u1"
},
{
"bug": 1132164,
"name": "python-ecdsa",
"type": "source",
"origin": null,
"release": "bookworm",
"urgency": "not yet assigned",
"fixed_version": ""
}
],
"distribution_packages": [
{
"name": "python-ecdsa",
"ecosystem": "cpe",
"fixed_version": "not yet fixed"
},
{
"name": "ecdsa",
"ecosystem": "cpe",
"fixed_version": "0.19.2"
},
{
"name": "ecdsa",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.19.2"
}
]
}
],
"ecosystem": "PyPI",
"fixed_version": "0.19.2",
"provider_record_id": "GHSA-9F5J-8JWJ-X28G"
},
{
"name": "python-ecdsa",
"distro": "opensuse",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.19.1-160000.4.1"
}
]
}
],
"release": "leap 16.0",
"versions": [],
"ecosystem": "rpm",
"fixed_version": "0.19.1-160000.4.1",
"provider_record_id": "OPENSUSE-SU-2026:21078-1"
},
{
"name": "python-ecdsa",
"distro": "suse",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.19.1-160000.4.1"
}
]
}
],
"release": "linux enterprise server 16.0",
"versions": [],
"ecosystem": "rpm",
"fixed_version": "0.19.1-160000.4.1",
"provider_record_id": "SUSE-SU-2026:22158-1"
},
{
"name": "python-ecdsa",
"distro": "suse",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.19.1-160000.4.1"
}
]
}
],
"release": "linux enterprise server for sap applications 16.0",
"versions": [],
"ecosystem": "rpm",
"fixed_version": "0.19.1-160000.4.1",
"provider_record_id": "SUSE-SU-2026:22158-1"
},
{
"name": "python-ecdsa",
"distro": "suse",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.13.3-150000.3.10.1"
}
]
}
],
"release": "linux enterprise module for basesystem 15 sp7",
"versions": [],
"ecosystem": "rpm",
"fixed_version": "0.13.3-150000.3.10.1",
"provider_record_id": "SUSE-SU-2026:1608-1"
},
{
"name": "python-ecdsa",
"distro": "suse",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.18.0-150400.12.6.1"
}
]
}
],
"release": "linux enterprise module for python 3 15 sp7",
"versions": [],
"ecosystem": "rpm",
"fixed_version": "0.18.0-150400.12.6.1",
"provider_record_id": "SUSE-SU-2026:1436-1"
},
{
"name": "python-ecdsa",
"distro": "opensuse",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.18.0-150400.12.6.1"
}
]
}
],
"release": "leap 15.6",
"versions": [],
"ecosystem": "rpm",
"fixed_version": "0.18.0-150400.12.6.1",
"provider_record_id": "SUSE-SU-2026:1436-1"
},
{
"name": "python-ecdsa",
"distro": "opensuse",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.19.2-1.1"
}
]
}
],
"release": "tumbleweed",
"versions": [],
"ecosystem": "rpm",
"fixed_version": "0.19.2-1.1",
"provider_record_id": "OPENSUSE-SU-2026:10468-1"
},
{
"name": "ecdsa",
"ranges": [
{
"fixed": "0.19.2",
"introduced": "",
"last_affected": "",
"start_excluding": ""
}
],
"ecosystem": "cpe",
"fixed_version": "0.19.2",
"provider_record_id": "NVD-CVE-2026-33936"
}
]
}Publisher notes
[bookworm] python-ecdsa: Minor issue
OpenFactory catalog packages
Matching against OpenFactory catalog package versions is in progress.
[Debian 12 (Bookworm)]
- [python3-ecdsa]Unknown
Source package: [python-ecdsa]
Details (2)
0.18.0-3· all · bookwormAffected
nvd · python-ecdsa · debian · bookworm; nvd · python-ecdsa · debian · 12
0.18.0-3· all · bookwormAffected
nvd · python-ecdsa · debian · bookworm; nvd · python-ecdsa · debian · 12
[Debian 13 (Trixie)]
- [python3-ecdsa]Unknown
Source package: [python-ecdsa]
Details (2)
0.19.1-1· all · trixieAffected · Fixed:
0.19.1-1+deb13u1nvd · python-ecdsa · debian · 13
0.19.1-1· all · trixieAffected · Fixed:
0.19.1-1+deb13u1nvd · python-ecdsa · debian · 13
[openSUSE Tumbleweed]
- [python313-ecdsa]Unknown
Source package: [python-ecdsa]
Details (1)
0.19.2-2.2· noarch · tumbleweedUnknown · Fixed:
0.19.2-1.1Version impact unknown
nvd · python-ecdsa · opensuse · tumbleweed
- [python314-ecdsa]Unknown
Source package: [python-ecdsa]
Details (1)
0.19.2-2.2· noarch · tumbleweedUnknown · Fixed:
0.19.2-1.1Version impact unknown
nvd · python-ecdsa · opensuse · tumbleweed
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/opensuse-su-2026_10468-1.json]
- [https://github.com/tlsfuzzer/python-ecdsa/commit/bd66899550d7185939bf27b75713a2ac9325a9d3]
- [https://github.com/tlsfuzzer/python-ecdsa/releases/tag/python-ecdsa-0.19.2]
- [https://github.com/tlsfuzzer/python-ecdsa/security/advisories/GHSA-9f5j-8jwj-x28g]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-33936]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-33936]
- [https://osv.dev/vulnerability/GHSA-9f5j-8jwj-x28g]
- [https://osv.dev/vulnerability/SUSE-SU-2026:1436-1]
- [https://osv.dev/vulnerability/SUSE-SU-2026:1608-1]
- [https://osv.dev/vulnerability/SUSE-SU-2026:22158-1]
- [https://osv.dev/vulnerability/openSUSE-SU-2026:10468-1]
- [https://osv.dev/vulnerability/openSUSE-SU-2026:21078-1]
- [https://security-tracker.debian.org/tracker/CVE-2026-33936]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33936.json]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]