CVE-2023-33953 (GCVE-0-2023-33953)

Vulnerability from cvelistv5 – Published: 2023-08-09 12:54 – Updated: 2024-09-27 18:40
VLAI
Title
Denial-of-Service in gRPC
Summary
gRPC contains a vulnerability that allows hpack table accounting errors could lead to unwanted disconnects between clients and servers in exceptional cases/ Three vectors were found that allow the following DOS attacks: - Unbounded memory buffering in the HPACK parser - Unbounded CPU consumption in the HPACK parser The unbounded CPU consumption is down to a copy that occurred per-input-block in the parser, and because that could be unbounded due to the memory copy bug we end up with an O(n^2) parsing loop, with n selected by the client. The unbounded memory buffering bugs: - The header size limit check was behind the string reading code, so we needed to first buffer up to a 4 gigabyte string before rejecting it as longer than 8 or 16kb. - HPACK varints have an encoding quirk whereby an infinite number of 0’s can be added at the start of an integer. gRPC’s hpack parser needed to read all of them before concluding a parse. - gRPC’s metadata overflow check was performed per frame, so that the following sequence of frames could cause infinite buffering: HEADERS: containing a: 1 CONTINUATION: containing a: 2 CONTINUATION: containing a: 3 etc…
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-834 - Excessive Iteration
  • CWE-789 - Memory Allocation with Excessive Size Value
Assigner
References
Impacted products
Vendor Product Version
Google gRPC Affected: 0 , < 1.56.1 (custom)
Create a notification for this product.
grpc grpc Affected: 0 , < 1.53.2 (custom)
Affected: 1.54 , < 154.3 (custom)
Affected: 1.55 , < 1.55.2 (custom)
Affected: 1.56 , < 1.56.2 (custom)
    cpe:2.3:a:grpc:grpc:*:*:*:*:*:*:*:*
 Create a notification for this product.
Show details on NVD website
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      "title": "gRPC: hpack table accounting errors can lead to denial of service",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-33953.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-06-28T01:14:50Z",
      "cve": "CVE-2023-33953",
      "id": "CVE-2023-33953",
      "initial_release_date": "2025-09-22T23:41:51Z",
      "product_status:known_affected": "162",
      "product_status:recommended": "156",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2023-33953",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2023-33953.json",
      "version": "11"
    },
    "vulnrichment": {
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client.\u003cbr\u003e\u003cbr\u003eThe unbounded memory buffering bugs:\u003cbr\u003e\u003cbr\u003e- The header size limit check was behind the string reading code, so we needed to first buffer up to a 4 gigabyte string before rejecting it as longer than 8 or 16kb.\u003cbr\u003e- HPACK varints have an encoding quirk whereby an infinite number of 0\\u2019s can be added at the start of an integer. gRPC\\u2019s hpack parser needed to read all of them before concluding a parse.\u003cbr\u003e- gRPC\\u2019s metadata overflow check was performed per frame, so that the following sequence of frames could cause infinite buffering: HEADERS: containing a: 1 CONTINUATION: containing a: 2 CONTINUATION: containing a: 3 etc\\u2026\"}], \"value\": \"gRPC contains a vulnerability that allows hpack table accounting errors could lead to unwanted disconnects between clients and servers in exceptional cases/\\u00a0Three vectors were found that allow the following DOS attacks:\\n\\n- Unbounded memory 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\"CAPEC-220\", \"descriptions\": [{\"lang\": \"en\", \"value\": \"CAPEC-220 Client-Server Protocol Manipulation\"}]}], \"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\"}, \"format\": \"CVSS\", \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"problemTypes\": [{\"descriptions\": [{\"cweId\": \"CWE-834\", \"description\": \"CWE-834 Excessive Iteration\", \"lang\": \"en\", \"type\": \"CWE\"}]}, {\"descriptions\": [{\"cweId\": \"CWE-789\", \"description\": \"CWE-789 Memory Allocation with Excessive Size Value\", \"lang\": \"en\", \"type\": \"CWE\"}]}], \"providerMetadata\": {\"orgId\": \"14ed7db2-1595-443d-9d34-6215bf890778\", \"shortName\": \"Google\", \"dateUpdated\": \"2023-08-09T12:54:47.415Z\"}, \"references\": [{\"url\": \"https://cloud.google.com/support/bulletins#gcp-2023-022\"}], \"source\": {\"discovery\": \"UNKNOWN\"}, \"title\": \"Denial-of-Service in gRPC\", \"x_generator\": {\"engine\": \"Vulnogram 0.1.0-dev\"}}, \"adp\": [{\"providerMetadata\": {\"orgId\": \"af854a3a-2127-422b-91ae-364da2661108\", \"shortName\": \"CVE\", \"dateUpdated\": \"2024-08-02T15:54:14.192Z\"}, \"title\": \"CVE Program Container\", \"references\": [{\"url\": \"https://cloud.google.com/support/bulletins#gcp-2023-022\", \"tags\": [\"x_transferred\"]}]}, {\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2023-33953\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2024-09-27T17:54:21.539206Z\"}}}], \"affected\": [{\"cpes\": [\"cpe:2.3:a:grpc:grpc:*:*:*:*:*:*:*:*\"], \"vendor\": \"grpc\", \"product\": \"grpc\", \"versions\": [{\"status\": \"affected\", \"version\": \"0\", \"lessThan\": \"1.53.2\", \"versionType\": \"custom\"}, {\"status\": \"affected\", \"version\": \"1.54\", \"lessThan\": \"154.3\", \"versionType\": \"custom\"}, {\"status\": \"affected\", \"version\": \"1.55\", \"lessThan\": \"1.55.2\", \"versionType\": \"custom\"}, {\"status\": \"affected\", \"version\": \"1.56\", \"lessThan\": \"1.56.2\", \"versionType\": \"custom\"}], \"defaultStatus\": \"unknown\"}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2024-09-27T18:40:44.014Z\"}}]}",
      "cveMetadata": "{\"cveId\": \"CVE-2023-33953\", \"assignerOrgId\": \"14ed7db2-1595-443d-9d34-6215bf890778\", \"state\": \"PUBLISHED\", \"assignerShortName\": \"Google\", \"dateReserved\": \"2023-05-24T12:08:31.409Z\", \"datePublished\": \"2023-08-09T12:54:47.415Z\", \"dateUpdated\": \"2024-09-27T18:40:52.297Z\"}",
      "dataType": "CVE_RECORD",
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}



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Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.


Detection rules are retrieved from Rulezet.