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
VLAI
EPSS
VEX
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
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-28 16:41 UTC
CWE
- CWE-476 - NULL Pointer Dereference
Assigner
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 | CPE status | |
|---|---|---|---|---|
| sdelements | lets-chat |
Affected:
0.4.0 , ≤ 0.4.8
(semver)
Affected: 84981a6d2534445c00ea4e095c934e46943c0b1d , ≤ 617207ff3c0c0bf8e3c7a915bd9ec03f1dd8390c (git) |
guessed |
Date Public
2026-07-26 00:00
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Sightings
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Nomenclature
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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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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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.