crypto: akcipher - default implementation for setting a private key

{
  "id": "79331048eacc2510cfde045ae8ae3c443eef296730d08d0deb5387cd966441fa",
  "url": "https://osv.dev/vulnerability/CVE-2022-50731",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "crypto: akcipher - default implementation for setting a private key",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: crypto: akcipher - default implementation for setting a private key Changes from v1: * removed the default implementation from set_pub_key: it is assumed that an implementation must always have this callback defined as there are no use case for an algorithm, which doesn't need a public key Many akcipher implementations (like ECDSA) support only signature verifications, so they don't have all callbacks defined. Commit 78a0324f4a53 (\"crypto: akcipher - default implementations for request callbacks\") introduced default callbacks for sign/verify operations, which just return an error code. However, these are not enough, because before calling sign the caller would likely call set_priv_key first on the instantiated transform (as the in-kernel testmgr does). This function does not have a default stub, so the kernel crashes, when trying to set a private key on an akcipher, which doesn't support signature generation. I've noticed this, when trying to add a KAT vector for ECDSA signature to the testmgr. With this patch the testmgr returns an error in dmesg (as it should) instead of crashing the kernel NULL ptr dereference.",
    "evidence": "osv:CVE-2022-50731",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.4.220",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.10.150",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.15.75",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.19.17",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.0.3",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2022-50731",
      "aliases": [
        "CVE-2022-50731"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "78a0324f4a5328088fea9426cfe1d1851276c475"
                },
                {
                  "fixed": "95c4e20adc3ea00d1594a2a05d9b187ed12ffa8e"
                },
                {
                  "fixed": "a1354bdd191d533211b7cb723aa76a66f516f197"
                },
                {
                  "fixed": "779a9930f3e152c82699feb389a0e6d6644e747e"
                },
                {
                  "fixed": "85bc736a18b872f54912e8bb70682d11770aece0"
                },
                {
                  "fixed": "f9058178597059d6307efe96a7916600f8ede08c"
                },
                {
                  "fixed": "bc155c6c188c2f0c5749993b1405673d25a80389"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-50731.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.2.0"
                },
                {
                  "fixed": "5.4.220"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.5.0"
                },
                {
                  "fixed": "5.10.150"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.11.0"
                },
                {
                  "fixed": "5.15.75"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "5.19.17"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.20.0"
                },
                {
                  "fixed": "6.0.3"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-50731.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:31.182584978Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/779a9930f3e152c82699feb389a0e6d6644e747e",
        "https://git.kernel.org/stable/c/85bc736a18b872f54912e8bb70682d11770aece0",
        "https://git.kernel.org/stable/c/95c4e20adc3ea00d1594a2a05d9b187ed12ffa8e",
        "https://git.kernel.org/stable/c/a1354bdd191d533211b7cb723aa76a66f516f197",
        "https://git.kernel.org/stable/c/bc155c6c188c2f0c5749993b1405673d25a80389",
        "https://git.kernel.org/stable/c/f9058178597059d6307efe96a7916600f8ede08c",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50731.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2022-50731",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50731.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2022-50731",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 498254,
  "published_at": "2025-12-24T12:22:51.122+00:00"
}