Vulnerability-Lookup

CVE-2026-59644 (GCVE-0-2026-59644)

Vulnerability from cvelistv5 – Published: 2026-08-03 00:50 – Updated: 2026-08-03 13:36

Title

MLS hash-ratchet honours arbitrary 32-bit generation counter from sender

Summary

In Bouncy Castle for Java before 1.85, MLS hash-ratchet honours arbitrary 32-bit generation counter from sender.

Severity

8.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/U:Amber

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-834 - Excessive Iteration

Assigner

bcorg

References

2 references

URL	Tags
https://github.com/bcgit/bc-java/wiki/CVE%E2%80%9…	vendor-advisory
https://github.com/bcgit/bc-java/commit/610d8757d…	patch

Impacted products

1 product

Vendor	Product	Version
Legion of the Bouncy Castle Inc.	BC-JAVA	Affected: 1.73 , < 1.85 (maven)

Credits

Alex Gaynor in collaboration with Claude and Anthropic Research

Show details on NVD website

JSON

To clipboard

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GHSA-XRMP-PCG8-5Q9V

Vulnerability from github – Published: 2026-08-03 03:31 – Updated: 2026-08-03 06:31

Details

In Bouncy Castle for Java before 1.85, MLS hash-ratchet honours arbitrary 32-bit generation counter from sender.

Severity

8.7 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/U:Amber

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-59644"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-834"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-03T01:16:44Z",
    "severity": "HIGH"
  },
  "details": "In Bouncy Castle for Java before 1.85, MLS hash-ratchet honours arbitrary 32-bit generation counter from sender.",
  "id": "GHSA-xrmp-pcg8-5q9v",
  "modified": "2026-08-03T06:31:42Z",
  "published": "2026-08-03T03:31:55Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-59644"
    },
    {
      "type": "WEB",
      "url": "https://github.com/bcgit/bc-java/commit/610d8757d855afe197df0de6d831cb75c81e3b9f"
    },
    {
      "type": "WEB",
      "url": "https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059644"
    },
    {
      "type": "WEB",
      "url": "https://github.com/bcgit/bc-java/wiki/CVE-2026-59644"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber",
      "type": "CVSS_V4"
    }
  ]
}

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.

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.

Action not permitted

CVE-2026-59644 (GCVE-0-2026-59644)

GHSA-XRMP-PCG8-5Q9V

Tags

Sightings

Nomenclature