Vulnerability-Lookup

CVE-2026-66749 (GCVE-0-2026-66749)

Vulnerability from cvelistv5 – Published: 2026-07-28 15:30 – Updated: 2026-07-28 16:43 X_Open Source Unsupported When Assigned

Title

Let's Chat 0.4.0 - 0.4.8 Denial of Service via Null Dereference in Room Lookup

Summary

Let's Chat 0.4.0 through 0.4.8 contains a null dereference vulnerability that allows authenticated attackers to crash the server by supplying a valid 24-character hex string room parameter that matches no document in the database. Attackers can send a crafted GET /messages request causing an uncaught TypeError in an asynchronous Mongoose callback that terminates the Node.js server process, with the same defect reachable through multiple code paths including the socket.io interface.

Severity

7.1 (High)


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

6.5 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-476 - NULL Pointer Dereference

Assigner

VulnCheck

References

2 references

URL	Tags
https://github.com/theopaid/Unchecked-Room-Lookup…	technical-descriptionexploit
https://www.vulncheck.com/advisories/let-s-chat-d…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
sdelements	lets-chat	Affected: 0.4.0 , ≤ 0.4.8 (semver) Affected: 84981a6d2534445c00ea4e095c934e46943c0b1d , ≤ 617207ff3c0c0bf8e3c7a915bd9ec03f1dd8390c (git)

Date Public

2026-07-26 00:00

Credits

Theodosis Paidakis

Show details on NVD website

JSON

To clipboard

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}

GHSA-QJPW-62VP-8J4Q

Vulnerability from github – Published: 2026-07-28 18:33 – Updated: 2026-07-28 18:33

Details

Severity

6.5 (Medium)


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

7.1 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-66749"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-28T16:20:16Z",
    "severity": "HIGH"
  },
  "details": "Let\u0027s Chat 0.4.0 through 0.4.8 contains a null dereference vulnerability that allows authenticated attackers to crash the server by supplying a valid 24-character hex string room parameter that matches no document in the database. Attackers can send a crafted GET /messages request causing an uncaught TypeError in an asynchronous Mongoose callback that terminates the Node.js server process, with the same defect reachable through multiple code paths including the socket.io interface.",
  "id": "GHSA-qjpw-62vp-8j4q",
  "modified": "2026-07-28T18:33:03Z",
  "published": "2026-07-28T18:33:02Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-66749"
    },
    {
      "type": "WEB",
      "url": "https://github.com/theopaid/Unchecked-Room-Lookup-Leads-to-Server-Crash-Let-s-Chat-"
    },
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      "url": "https://www.vulncheck.com/advisories/let-s-chat-denial-of-service-via-null-dereference-in-room-lookup"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/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:X",
      "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-2026-66749 (GCVE-0-2026-66749)

GHSA-QJPW-62VP-8J4Q

Tags

Sightings

Nomenclature