pysec - pysec-2019-177

pysec-2019-177

Vulnerability from pysec

Published

2019-11-26 13:15

Modified

2021-08-27 03:22

Details

An error-handling flaw was found in python-ecdsa before version 0.13.3. During signature decoding, malformed DER signatures could raise unexpected exceptions (or no exceptions at all), which could lead to a denial of service.

Impacted products

Name	purl
ecdsa	pkg:pypi/ecdsa

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "ecdsa",
        "purl": "pkg:pypi/ecdsa"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.13.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.10",
        "0.11",
        "0.12",
        "0.13",
        "0.13.1",
        "0.13.2",
        "0.6",
        "0.7",
        "0.8",
        "0.9"
      ]
    }
  ],
  "aliases": [
    "CVE-2019-14853",
    "GHSA-2mrj-435v-c2cr",
    "GHSA-pwfw-mgfj-7g3g"
  ],
  "details": "An error-handling flaw was found in python-ecdsa before version 0.13.3. During signature decoding, malformed DER signatures could raise unexpected exceptions (or no exceptions at all), which could lead to a denial of service.",
  "id": "PYSEC-2019-177",
  "modified": "2021-08-27T03:22:03.507805Z",
  "published": "2019-11-26T13:15:00Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/warner/python-ecdsa/releases/tag/python-ecdsa-0.13.3"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14853"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.debian.org/security/2019/dsa-4588"
    },
    {
      "type": "WEB",
      "url": "https://seclists.org/bugtraq/2019/Dec/33"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-2mrj-435v-c2cr"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-pwfw-mgfj-7g3g"
    }
  ]
}

ghsa-pwfw-mgfj-7g3g

Vulnerability from github

Published

2019-10-08 16:30

Modified

2024-09-20 16:47

Severity ?

7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.7 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Summary

ecdsa Denial of Service vulnerability in signature verification and signature malleability

Details

possible DoS in signature verification and signature malleability

Impact

Code using VerifyingKey.verify() and VerifyingKey.verify_digest() may receive exceptions other than the documented BadSignatureError when signatures are malformed. If those other exceptions are not caught, they may lead to program termination and thus Denial of Service

Code using VerifyingKey.verify() and VerifyingKey.verify_digest() with sigdecode option using ecdsa.util.sigdecode_der will accept signatures even if they are not properly formatted DER. This makes the signatures malleable. It impacts only applications that later sign the signatures or verify signatures of signatures, e.g. Bitcoin.

All versions between 0.5 and 0.13.2 (inclusive) are thought to be vulnerable. Code before 0.5 may be vulnerable but didn't receive extended analysis to rule this issue out.

Patches

The patches have been merged to master branch in https://github.com/warner/python-ecdsa/pull/115. The backported patches for a release in the 0.13 branch are in https://github.com/warner/python-ecdsa/pull/124

They are part of the 0.13.3 release.

There are no plans to backport them to earlier releases.

Workarounds

It may be possible to prevent the Denial of Service by catching also UnexpectedDER, IndexError and AssertionError exceptions. That list hasn't been verified to be complete though. If those exceptions are raised, the signature verification process should consider the signature to be invalid.

To remediate signature malleability and the Denial of Service vulnerability, it may be possible to first verify that the signature is properly DER formatted ECDSA-Sig-Value, as defined in RFC3279, before passing it to verify() or verify_digest() methods. If the signature is determined to not follow the DER or encode a different structure, the signature verification process should consider the signature to be invalid.

References

https://en.bitcoinwiki.org/wiki/Transaction_Malleability

For more information

If you have any questions or comments about this advisory please open an issue in python-ecdsa project.

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "ecdsa"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.13.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2019-14853"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-391",
      "CWE-755"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2020-06-16T20:41:53Z",
    "nvd_published_at": "2019-11-26T13:15:00Z",
    "severity": "HIGH"
  },
  "details": "## possible DoS in signature verification and signature malleability \n\n### Impact\nCode using `VerifyingKey.verify()` and `VerifyingKey.verify_digest()` may receive exceptions other than the documented `BadSignatureError` when signatures are malformed. If those other exceptions are not caught, they may lead to program termination and thus Denial of Service\n\nCode using `VerifyingKey.verify()` and `VerifyingKey.verify_digest()` with `sigdecode` option using `ecdsa.util.sigdecode_der` will accept signatures even if they are not properly formatted DER. This makes the signatures malleable. It impacts only applications that later sign the signatures or verify signatures of signatures, e.g. Bitcoin.\n\nAll versions between 0.5 and 0.13.2 (inclusive) are thought to be vulnerable. Code before 0.5 may be vulnerable but didn\u0027t receive extended analysis to rule this issue out.\n\n### Patches\nThe patches have been merged to `master` branch in https://github.com/warner/python-ecdsa/pull/115.\nThe backported patches for a release in the 0.13 branch are in https://github.com/warner/python-ecdsa/pull/124\n\nThey are part of the 0.13.3 release.\n\nThere are no plans to backport them to earlier releases.\n\n### Workarounds\nIt may be possible to prevent the Denial of Service by catching also `UnexpectedDER`, `IndexError` and `AssertionError` exceptions. That list hasn\u0027t been verified to be complete though. If those exceptions are raised, the signature verification process should consider the signature to be invalid.\n\nTo remediate signature malleability and the Denial of Service vulnerability, it may be possible to first verify that the signature is properly DER formatted ECDSA-Sig-Value, as defined in [RFC3279](https://tools.ietf.org/html/rfc3279), before passing it to `verify()` or `verify_digest()` methods. If the signature is determined to not follow the DER or encode a different structure, the signature verification process should consider the signature to be invalid.\n\n### References\nhttps://en.bitcoinwiki.org/wiki/Transaction_Malleability\n\n### For more information\nIf you have any questions or comments about this advisory please open an issue in [python-ecdsa](https://github.com/warner/python-ecdsa/issues) project.\n",
  "id": "GHSA-pwfw-mgfj-7g3g",
  "modified": "2024-09-20T16:47:14Z",
  "published": "2019-10-08T16:30:17Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/warner/python-ecdsa/security/advisories/GHSA-pwfw-mgfj-7g3g"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-14853"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14853"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/ecdsa/PYSEC-2019-177.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/warner/python-ecdsa"
    },
    {
      "type": "WEB",
      "url": "https://github.com/warner/python-ecdsa/releases/tag/python-ecdsa-0.13.3"
    },
    {
      "type": "WEB",
      "url": "https://seclists.org/bugtraq/2019/Dec/33"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2019/dsa-4588"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "ecdsa Denial of Service vulnerability in signature verification and signature malleability"
}

ghsa-2mrj-435v-c2cr

Vulnerability from github

Published

2019-12-02 18:15

Modified

2024-09-20 16:46

Summary

Duplicate Advisory: possible DoS caused by malformed signature decoding in Pure-Python ECDSA

Details

Duplicate Advisory

This advisory has been withdrawn because it is a duplicate of GHSA-pwfw-mgfj-7g3g. This link is maintained to preserve external references.

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "ecdsa"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.13.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": true,
    "github_reviewed_at": "2019-12-02T01:15:50Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "## Duplicate Advisory\nThis advisory has been withdrawn because it is a duplicate of GHSA-pwfw-mgfj-7g3g. This link is maintained to preserve external references.",
  "id": "GHSA-2mrj-435v-c2cr",
  "modified": "2024-09-20T16:46:32Z",
  "published": "2019-12-02T18:15:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-14853"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14853"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-2mrj-435v-c2cr"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-pwfw-mgfj-7g3g"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/ecdsa/PYSEC-2019-177.yaml"
    },
    {
      "type": "WEB",
      "url": "https://github.com/warner/python-ecdsa/releases/tag/python-ecdsa-0.13.3"
    },
    {
      "type": "WEB",
      "url": "https://seclists.org/bugtraq/2019/Dec/33"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2019/dsa-4588"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [],
  "summary": "Duplicate Advisory: possible DoS caused by malformed signature decoding in Pure-Python ECDSA",
  "withdrawn": "2020-06-16T20:15:24Z"
}

CVE-2019-14853 (GCVE-0-2019-14853)

Vulnerability from cvelistv5

Published

2019-11-26 12:06

Modified

2024-08-05 00:26

Severity ?

3.7 (Low) - CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

CWE

CWE-391

Summary

References

URL

Tags

	https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14853	x_refsource_CONFIRM
	https://github.com/warner/python-ecdsa/releases/tag/python-ecdsa-0.13.3	x_refsource_MISC
	https://www.debian.org/security/2019/dsa-4588	vendor-advisory, x_refsource_DEBIAN
	https://seclists.org/bugtraq/2019/Dec/33	mailing-list, x_refsource_BUGTRAQ

Impacted products

	Vendor	Product	Version
	[UNKNOWN]	python-ecdsa	Version: 0.13.3

Show details on NVD website

JSON

To clipboard

{
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          "dateUpdated": "2024-08-05T00:26:39.175Z",
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            "url": "https://github.com/warner/python-ecdsa/releases/tag/python-ecdsa-0.13.3"
          },
          {
            "name": "DSA-4588",
            "tags": [
              "vendor-advisory",
              "x_refsource_DEBIAN",
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            "url": "https://www.debian.org/security/2019/dsa-4588"
          },
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            "name": "20191218 [SECURITY] [DSA 4588-1] python-ecdsa security update",
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        "title": "CVE Program Container"
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    ],
    "cna": {
      "affected": [
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          "product": "python-ecdsa",
          "vendor": "[UNKNOWN]",
          "versions": [
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              "version": "0.13.3"
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          ]
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      ],
      "descriptions": [
        {
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      ],
      "metrics": [
        {
          "cvssV3_0": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 3.7,
            "baseSeverity": "LOW",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L",
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      "problemTypes": [
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}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
Confirmed: The vulnerability is confirmed from an analyst perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
Patched: This vulnerability was successfully patched by the user reporting the sighting.
Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
Not confirmed: The user expresses doubt about the veracity of the vulnerability.
Not patched: This vulnerability was not successfully patched by the user reporting the sighting.

Action not permitted

pysec-2019-177

Vulnerability from pysec

ghsa-pwfw-mgfj-7g3g

Vulnerability from github

possible DoS in signature verification and signature malleability

Impact

Patches

Workarounds

References

For more information

ghsa-2mrj-435v-c2cr

Vulnerability from github

Duplicate Advisory

CVE-2019-14853 (GCVE-0-2019-14853)

Vulnerability from cvelistv5

Tags

Sightings

Nomenclature