CVE-2021-21404
Vulnerability from cvelistv5
Published
2021-04-06 20:00
Modified
2024-08-03 18:09
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
Syncthing is a continuous file synchronization program. In Syncthing before version 1.15.0, the relay server `strelaysrv` can be caused to crash and exit by sending a relay message with a negative length field. Similarly, Syncthing itself can crash for the same reason if given a malformed message from a malicious relay server when attempting to join the relay. Relay joins are essentially random (from a subset of low latency relays) and Syncthing will by default restart when crashing, at which point it's likely to pick another non-malicious relay. This flaw is fixed in version 1.15.0.
References
security-advisories@github.comhttps://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97Patch, Third Party Advisory
security-advisories@github.comhttps://github.com/syncthing/syncthing/releases/tag/v1.15.0Release Notes, Third Party Advisory
security-advisories@github.comhttps://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5hThird Party Advisory
security-advisories@github.comhttps://pkg.go.dev/github.com/syncthing/syncthingProduct, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/syncthing/syncthing/releases/tag/v1.15.0Release Notes, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5hThird Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://pkg.go.dev/github.com/syncthing/syncthingProduct, Third Party Advisory
Impacted products
Vendor Product Version
syncthing syncthing Version: < 1.15.0
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
   containers: {
      adp: [
         {
            providerMetadata: {
               dateUpdated: "2024-08-03T18:09:16.158Z",
               orgId: "af854a3a-2127-422b-91ae-364da2661108",
               shortName: "CVE",
            },
            references: [
               {
                  tags: [
                     "x_refsource_CONFIRM",
                     "x_transferred",
                  ],
                  url: "https://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5h",
               },
               {
                  tags: [
                     "x_refsource_MISC",
                     "x_transferred",
                  ],
                  url: "https://pkg.go.dev/github.com/syncthing/syncthing",
               },
               {
                  tags: [
                     "x_refsource_MISC",
                     "x_transferred",
                  ],
                  url: "https://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97",
               },
               {
                  tags: [
                     "x_refsource_MISC",
                     "x_transferred",
                  ],
                  url: "https://github.com/syncthing/syncthing/releases/tag/v1.15.0",
               },
            ],
            title: "CVE Program Container",
         },
      ],
      cna: {
         affected: [
            {
               product: "syncthing",
               vendor: "syncthing",
               versions: [
                  {
                     status: "affected",
                     version: "< 1.15.0",
                  },
               ],
            },
         ],
         descriptions: [
            {
               lang: "en",
               value: "Syncthing is a continuous file synchronization program. In Syncthing before version 1.15.0, the relay server `strelaysrv` can be caused to crash and exit by sending a relay message with a negative length field. Similarly, Syncthing itself can crash for the same reason if given a malformed message from a malicious relay server when attempting to join the relay. Relay joins are essentially random (from a subset of low latency relays) and Syncthing will by default restart when crashing, at which point it's likely to pick another non-malicious relay. This flaw is fixed in version 1.15.0.",
            },
         ],
         metrics: [
            {
               cvssV3_1: {
                  attackComplexity: "LOW",
                  attackVector: "NETWORK",
                  availabilityImpact: "HIGH",
                  baseScore: 7.5,
                  baseSeverity: "HIGH",
                  confidentialityImpact: "NONE",
                  integrityImpact: "NONE",
                  privilegesRequired: "NONE",
                  scope: "UNCHANGED",
                  userInteraction: "NONE",
                  vectorString: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  version: "3.1",
               },
            },
         ],
         problemTypes: [
            {
               descriptions: [
                  {
                     cweId: "CWE-20",
                     description: "CWE-20 Improper Input Validation",
                     lang: "en",
                     type: "CWE",
                  },
               ],
            },
         ],
         providerMetadata: {
            dateUpdated: "2021-04-06T20:00:15",
            orgId: "a0819718-46f1-4df5-94e2-005712e83aaa",
            shortName: "GitHub_M",
         },
         references: [
            {
               tags: [
                  "x_refsource_CONFIRM",
               ],
               url: "https://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5h",
            },
            {
               tags: [
                  "x_refsource_MISC",
               ],
               url: "https://pkg.go.dev/github.com/syncthing/syncthing",
            },
            {
               tags: [
                  "x_refsource_MISC",
               ],
               url: "https://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97",
            },
            {
               tags: [
                  "x_refsource_MISC",
               ],
               url: "https://github.com/syncthing/syncthing/releases/tag/v1.15.0",
            },
         ],
         source: {
            advisory: "GHSA-x462-89pf-6r5h",
            discovery: "UNKNOWN",
         },
         title: "Crash due to malformed relay protocol message",
         x_legacyV4Record: {
            CVE_data_meta: {
               ASSIGNER: "security-advisories@github.com",
               ID: "CVE-2021-21404",
               STATE: "PUBLIC",
               TITLE: "Crash due to malformed relay protocol message",
            },
            affects: {
               vendor: {
                  vendor_data: [
                     {
                        product: {
                           product_data: [
                              {
                                 product_name: "syncthing",
                                 version: {
                                    version_data: [
                                       {
                                          version_value: "< 1.15.0",
                                       },
                                    ],
                                 },
                              },
                           ],
                        },
                        vendor_name: "syncthing",
                     },
                  ],
               },
            },
            data_format: "MITRE",
            data_type: "CVE",
            data_version: "4.0",
            description: {
               description_data: [
                  {
                     lang: "eng",
                     value: "Syncthing is a continuous file synchronization program. In Syncthing before version 1.15.0, the relay server `strelaysrv` can be caused to crash and exit by sending a relay message with a negative length field. Similarly, Syncthing itself can crash for the same reason if given a malformed message from a malicious relay server when attempting to join the relay. Relay joins are essentially random (from a subset of low latency relays) and Syncthing will by default restart when crashing, at which point it's likely to pick another non-malicious relay. This flaw is fixed in version 1.15.0.",
                  },
               ],
            },
            impact: {
               cvss: {
                  attackComplexity: "LOW",
                  attackVector: "NETWORK",
                  availabilityImpact: "HIGH",
                  baseScore: 7.5,
                  baseSeverity: "HIGH",
                  confidentialityImpact: "NONE",
                  integrityImpact: "NONE",
                  privilegesRequired: "NONE",
                  scope: "UNCHANGED",
                  userInteraction: "NONE",
                  vectorString: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  version: "3.1",
               },
            },
            problemtype: {
               problemtype_data: [
                  {
                     description: [
                        {
                           lang: "eng",
                           value: "CWE-20 Improper Input Validation",
                        },
                     ],
                  },
               ],
            },
            references: {
               reference_data: [
                  {
                     name: "https://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5h",
                     refsource: "CONFIRM",
                     url: "https://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5h",
                  },
                  {
                     name: "https://pkg.go.dev/github.com/syncthing/syncthing",
                     refsource: "MISC",
                     url: "https://pkg.go.dev/github.com/syncthing/syncthing",
                  },
                  {
                     name: "https://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97",
                     refsource: "MISC",
                     url: "https://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97",
                  },
                  {
                     name: "https://github.com/syncthing/syncthing/releases/tag/v1.15.0",
                     refsource: "MISC",
                     url: "https://github.com/syncthing/syncthing/releases/tag/v1.15.0",
                  },
               ],
            },
            source: {
               advisory: "GHSA-x462-89pf-6r5h",
               discovery: "UNKNOWN",
            },
         },
      },
   },
   cveMetadata: {
      assignerOrgId: "a0819718-46f1-4df5-94e2-005712e83aaa",
      assignerShortName: "GitHub_M",
      cveId: "CVE-2021-21404",
      datePublished: "2021-04-06T20:00:15",
      dateReserved: "2020-12-22T00:00:00",
      dateUpdated: "2024-08-03T18:09:16.158Z",
      state: "PUBLISHED",
   },
   dataType: "CVE_RECORD",
   dataVersion: "5.1",
   "vulnerability-lookup:meta": {
      nvd: "{\"cve\":{\"id\":\"CVE-2021-21404\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2021-04-06T20:15:13.490\",\"lastModified\":\"2024-11-21T05:48:17.280\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Syncthing is a continuous file synchronization program. In Syncthing before version 1.15.0, the relay server `strelaysrv` can be caused to crash and exit by sending a relay message with a negative length field. Similarly, Syncthing itself can crash for the same reason if given a malformed message from a malicious relay server when attempting to join the relay. Relay joins are essentially random (from a subset of low latency relays) and Syncthing will by default restart when crashing, at which point it's likely to pick another non-malicious relay. This flaw is fixed in version 1.15.0.\"},{\"lang\":\"es\",\"value\":\"Syncthing es un programa de sincronización de archivos continua.&#xa0;En Syncthing versiones anteriores a 1.15.0, el servidor de retransmisión \\\"strelaysrv\\\" puede causar un bloqueo y salida mediante el envío de un mensaje de retransmisión con un campo de longitud negativa.&#xa0;De manera similar, Syncthing en sí puede presentar un fallo por la misma razón si recibe un mensaje malformado de un servidor de retransmisión malicioso al intentar unirse a la retransmisión.&#xa0;Las uniones de retransmisiones son esencialmente aleatorias (de un subconjunto de retransmisiones de baja latencia) y Syncthing se reiniciará por defecto cuando se bloquee, momento en el que es probable que elija otra retransmisión no maliciosa.&#xa0;Este fallo es corregido en la versión 1.15.0\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}],\"cvssMetricV2\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"2.0\",\"vectorString\":\"AV:N/AC:L/Au:N/C:N/I:N/A:P\",\"baseScore\":5.0,\"accessVector\":\"NETWORK\",\"accessComplexity\":\"LOW\",\"authentication\":\"NONE\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"PARTIAL\"},\"baseSeverity\":\"MEDIUM\",\"exploitabilityScore\":10.0,\"impactScore\":2.9,\"acInsufInfo\":false,\"obtainAllPrivilege\":false,\"obtainUserPrivilege\":false,\"obtainOtherPrivilege\":false,\"userInteractionRequired\":false}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-20\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:syncthing:syncthing:*:*:*:*:*:*:*:*\",\"versionEndExcluding\":\"1.15.0\",\"matchCriteriaId\":\"13E0DFD1-14D6-4A2D-B98C-1C581D11E2F0\"}]}]}],\"references\":[{\"url\":\"https://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/syncthing/syncthing/releases/tag/v1.15.0\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Release Notes\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5h\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"https://pkg.go.dev/github.com/syncthing/syncthing\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Product\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/syncthing/syncthing/commit/fb4fdaf4c0a79c22cad000c42ac1394e3ccb6a97\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/syncthing/syncthing/releases/tag/v1.15.0\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Release Notes\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/syncthing/syncthing/security/advisories/GHSA-x462-89pf-6r5h\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"https://pkg.go.dev/github.com/syncthing/syncthing\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Product\",\"Third Party Advisory\"]}]}}",
   },
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




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.
  • 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.