Vulnerability-Lookup

(CVE-2026-84784)

Vulnerability from cleanstart – Published: 2026-10-22 00:42 – Updated: 2026-10-21 08:19 – Source website

Summary

Issue summary: A malicious remote peer may flood the local QUIC stack with NEW_CONNECTION_ID frames by avoiding a limit check on how many connection IDs the remote QUIC stack can use

Details

CVE-2026-84784 affects multiple packages. Issue summary: A malicious remote peer may flood the local QUIC stack with NEW_CONNECTION_ID frames by avoiding a limit check on how many connection IDs the remote QUIC stack can use. See references for individual vulnerability details.

Severity

7.5 (High)


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

References

URL

Type

	https://github.com/cleanstart-dev/cleanstart-secu…	ADVISORY
	https://osv.dev/vulnerability/CVE-2026-84784	WEB
	https://nvd.nist.gov/vuln/detail/CVE-2026-84784	WEB

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "CleanStart",
        "name": "miniforge3",
        "purl": "pkg:apk/cleanstart/miniforge3?arch=x86_64"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "26.3.2.0-r2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
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        "name": "miniforge3",
        "purl": "pkg:apk/cleanstart/miniforge3?arch=aarch64"
      },
      "ranges": [
        {
          "events": [
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            },
            {
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        }
      ]
    },
    {
      "package": {
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        "name": "miniforge3",
        "purl": "pkg:apk/cleanstart/miniforge3?arch=x86_64"
      },
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            },
            {
              "fixed": "26.3.2.3-r3"
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        }
      ]
    },
    {
      "package": {
        "ecosystem": "CleanStart",
        "name": "miniforge3",
        "purl": "pkg:apk/cleanstart/miniforge3?arch=aarch64"
      },
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        {
          "events": [
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              "introduced": "0"
            },
            {
              "fixed": "26.3.2.3-r3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "CleanStart",
        "name": "miniforge3",
        "purl": "pkg:apk/cleanstart/miniforge3?arch=x86_64"
      },
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            }
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        }
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    },
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        "ecosystem": "CleanStart",
        "name": "miniforge3",
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      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "26.1.1.3-r2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [],
  "database_specific": {},
  "details": "CVE-2026-84784 affects multiple packages. Issue summary: A malicious remote peer may flood the local QUIC stack with NEW_CONNECTION_ID frames by avoiding a limit check on how many connection IDs the remote QUIC stack can use. See references for individual vulnerability details.",
  "id": "CLEANSTART-2026-DG48545",
  "modified": "2026-10-21T08:19:00Z",
  "published": "2026-10-22T00:42:38.627634Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/cleanstart-dev/cleanstart-security-advisories/tree/main/advisories/2026/CLEANSTART-2026-DG48545.json"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-84784"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84784"
    }
  ],
  "related": [],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Issue summary: A malicious remote peer may flood the local QUIC\nstack with NEW_CONNECTION_ID frames by avoiding a limit check on\nhow many connection IDs the remote QUIC stack can use",
  "upstream": [
    "CVE-2026-84784"
  ]
}

CVE-2026-84784 (GCVE-0-2026-84784)

Vulnerability from cvelistv5 – Published: 2026-09-29 15:32 – Updated: 2026-09-29 16:44

Title

QUIC: Unbounded RETIRE_CONNECTION_ID Backlog

Summary

Issue summary: A malicious remote peer may flood the local QUIC stack with NEW_CONNECTION_ID frames by avoiding a limit check on how many connection IDs the remote QUIC stack can use. Impact summary: The local QUIC stack sends a RETIRE_CONN_ID frame for every NEW_CONNECTION_ID frame it receives. The RETIRE_CONN_ID frame is dispatched via the Control Frame Queue (CFQ). If the remote peer also withholds ACKs, then it can force the local stack to allocate ~400MB (depending on ACK delay). CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: RFC 9000 sections 5.1.1 and 5.1.2 [1] describe the mechanism by which a remote peer can notify the local QUIC stack to change the destination connection ID (a.k.a. CID) the local stack uses to identify the connection at the remote peer. Each CID is associated with a sequence number. The sequence number is transmitted in NEW_CONNECTION_ID and RETIRE_CONNECTION_ID frames to identify the CID which is being either associated with a connection or retired. The remote peer sends a NEW_CONNECTION_ID frame to let the local stack know a new CID is being associated with an existing connection. The NEW_CONNECTION_ID frame carries the new CID, its sequence number, and the retire-prior-to number. The retire-prior-to identifies existing CIDs that are to be retired. The local QUIC stack must send a RETIRE_CONNECTION_ID for every destination CID whose sequence number is less than retire-prior-to. The CID becomes retired after the local stack receives an ACK for its RETIRE_CONNECTION_ID frame. Although the OpenSSL QUIC stack supports at most one destination CID for every connection, it can be tricked into processing more than one RETIRE_CONNECTION_ID frame per connection. The OpenSSL QUIC stack currently retires the destination CID as soon as it receives the NEW_CONNECTION_ID, while in fact the destination CID must be retired after an ACK for the RETIRE_CONNECTION_ID frame is received. Correcting the flawed logic also fixes the backlog growth. [1] https://datatracker.ietf.org/doc/html/rfc9000#name-issuing-connection-ids FIPS impact: no The FIPS module is not affected as the QUIC implementation is outside of the OpenSSL FIPS module boundary.

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 · CISA-ADP (v2.0.3)

Decision recorded 2026-09-29 16:43 UTC

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

openssl CNA under the mitre root

CNA scorecard B 78/100 over 43 records in the last 180 days details

References

5 references

URL	Tags
https://openssl-library.org/news/secadv/20260929.txt	vendor-advisory
https://github.com/openssl/openssl/commit/e9e5155…	patch
https://github.com/openssl/openssl/commit/4685c91…	patch
https://github.com/openssl/openssl/commit/dba3c48…	patch
https://github.com/openssl/openssl/commit/9a30fe0…	patch

Impacted products

1 product

Vendor	Product	Version
OpenSSL	OpenSSL	Affected: 4.0.0 , < 4.0.3 (semver) Affected: 3.6.0 , < 3.6.5 (semver) Affected: 3.5.0 , < 3.5.9 (semver) Affected: 3.4.0 , < 3.4.8 (semver)

Date Public

2026-09-29 14:21

Credits

Bhabani Sankar Das Alexandr Nedvedicky

Show details on NVD website

JSON

To clipboard

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          {
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              "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",
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                "options": [
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                  },
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                "timestamp": "2026-09-29T16:43:47.766260Z",
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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          "defaultStatus": "unaffected",
          "product": "OpenSSL",
          "vendor": "OpenSSL",
          "versions": [
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              "lessThan": "4.0.3",
              "status": "affected",
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              "versionType": "semver"
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              "status": "affected",
              "version": "3.6.0",
              "versionType": "semver"
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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.

Vulnerability timeline

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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.
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