Vulnerability-Lookup

OESA-2021-1362 (CVE-2021-40528)

Vulnerability from osv_openeuler – Published: 2021-09-30 11:04 – Updated: 2026-08-06 11:04 – Source website

Summary

libgcrypt security update

Details

Libgcrypt is a general purpose cryptographic library originally based on code from GnuPG.

Security Fix(es):

The ElGamal implementation in Libgcrypt before 1.9.4 allows plaintext recovery because, during interaction between two cryptographic libraries, a certain dangerous combination of the prime defined by the receiver's public key, the generator defined by the receiver's public key, and the sender's ephemeral exponents can lead to a cross-configuration attack against OpenPGP.(CVE-2021-40528)

Severity

5.9 (Medium)


                    
                      CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

References

URL

Type

	https://www.openeuler.org/en/security/safety-bull…	ADVISORY
	https://nvd.nist.gov/vuln/detail/CVE-2021-40528	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "libgcrypt-1.8.6-4.oe1.aarch64.rpm",
          "libgcrypt-debuginfo-1.8.6-4.oe1.aarch64.rpm",
          "libgcrypt-devel-1.8.6-4.oe1.aarch64.rpm",
          "libgcrypt-debugsource-1.8.6-4.oe1.aarch64.rpm"
        ],
        "noarch": [
          "libgcrypt-help-1.8.6-4.oe1.noarch.rpm"
        ],
        "src": [
          "libgcrypt-1.8.6-4.oe1.src.rpm"
        ],
        "x86_64": [
          "libgcrypt-debugsource-1.8.6-4.oe1.x86_64.rpm",
          "libgcrypt-debuginfo-1.8.6-4.oe1.x86_64.rpm",
          "libgcrypt-1.8.6-4.oe1.x86_64.rpm",
          "libgcrypt-devel-1.8.6-4.oe1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP1",
        "name": "libgcrypt",
        "purl": "pkg:rpm/openEuler/libgcrypt\u0026distro=openEuler-20.03-LTS-SP1"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.8.6-4.oe1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "libgcrypt-devel-1.8.6-4.oe1.aarch64.rpm",
          "libgcrypt-1.8.6-4.oe1.aarch64.rpm",
          "libgcrypt-debugsource-1.8.6-4.oe1.aarch64.rpm",
          "libgcrypt-debuginfo-1.8.6-4.oe1.aarch64.rpm"
        ],
        "noarch": [
          "libgcrypt-help-1.8.6-4.oe1.noarch.rpm"
        ],
        "src": [
          "libgcrypt-1.8.6-4.oe1.src.rpm"
        ],
        "x86_64": [
          "libgcrypt-1.8.6-4.oe1.x86_64.rpm",
          "libgcrypt-debugsource-1.8.6-4.oe1.x86_64.rpm",
          "libgcrypt-debuginfo-1.8.6-4.oe1.x86_64.rpm",
          "libgcrypt-devel-1.8.6-4.oe1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP2",
        "name": "libgcrypt",
        "purl": "pkg:rpm/openEuler/libgcrypt\u0026distro=openEuler-20.03-LTS-SP2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.8.6-4.oe1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "Medium"
  },
  "details": "Libgcrypt is a general purpose cryptographic library originally based on code from GnuPG.\r\n\r\nSecurity Fix(es):\r\n\r\nThe ElGamal implementation in Libgcrypt before 1.9.4 allows plaintext recovery because, during interaction between two cryptographic libraries, a certain dangerous combination of the prime defined by the receiver\u0026apos;s public key, the generator defined by the receiver\u0026apos;s public key, and the sender\u0026apos;s ephemeral exponents can lead to a cross-configuration attack against OpenPGP.(CVE-2021-40528)",
  "id": "OESA-2021-1362",
  "modified": "2026-08-06T11:04:38Z",
  "published": "2021-09-30T11:04:38Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2021-1362"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-40528"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "libgcrypt security update",
  "upstream": [
    "CVE-2021-40528"
  ]
}

CVE-2021-40528 (GCVE-0-2021-40528)

Vulnerability from cvelistv5 – Published: 2021-09-06 00:00 – Updated: 2025-06-09 15:13

Summary

Severity

5.9 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-06-09 15:12 UTC

CWE

n/a
CWE-327 - Use of a Broken or Risky Cryptographic Algorithm

Assigner

mitre mitre root

References

5 references

URL	Tags
https://eprint.iacr.org/2021/923
https://ibm.github.io/system-security-research-up…
https://ibm.github.io/system-security-research-up…
https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcr…
https://security.gentoo.org/glsa/202210-13	vendor-advisory

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-04T02:44:10.845Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
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            ],
            "url": "https://eprint.iacr.org/2021/923"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=3462280f2e23e16adf3ed5176e0f2413d8861320"
          },
          {
            "name": "GLSA-202210-13",
            "tags": [
              "vendor-advisory",
              "x_transferred"
            ],
            "url": "https://security.gentoo.org/glsa/202210-13"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "HIGH",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 5.9,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2021-40528",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-06-09T15:12:20.359985Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
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            "descriptions": [
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                "description": "CWE-327 Use of a Broken or Risky Cryptographic Algorithm",
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                "type": "CWE"
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        ],
        "providerMetadata": {
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
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              "version": "n/a"
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      ],
      "descriptions": [
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        }
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      "problemTypes": [
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      "providerMetadata": {
        "dateUpdated": "2022-10-31T00:00:00.000Z",
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      "references": [
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          "url": "https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2"
        },
        {
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        },
        {
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          "url": "https://security.gentoo.org/glsa/202210-13"
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  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
    "assignerShortName": "mitre",
    "cveId": "CVE-2021-40528",
    "datePublished": "2021-09-06T00:00:00.000Z",
    "dateReserved": "2021-09-06T00:00:00.000Z",
    "dateUpdated": "2025-06-09T15:13:03.906Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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Action not permitted

OESA-2021-1362 (CVE-2021-40528)

CVE-2021-40528 (GCVE-0-2021-40528)

Tags

Sightings

Nomenclature

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