Vulnerability-Lookup

GHSA-CHP4-5883-3F2X

Vulnerability from github – Published: 2026-01-15 18:31 – Updated: 2026-01-15 18:31

Details

AbsoluteTelnet 11.24 contains a denial of service vulnerability that allows local attackers to crash the application by manipulating username and error report fields. Attackers can trigger the crash by inserting 1000 characters into the username or email address fields, causing the application to become unresponsive.

Severity

6.2 (Medium)


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

6.7 (Medium)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2021-47765"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-787"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-01-15T16:16:07Z",
    "severity": "MODERATE"
  },
  "details": "AbsoluteTelnet 11.24 contains a denial of service vulnerability that allows local attackers to crash the application by manipulating username and error report fields. Attackers can trigger the crash by inserting 1000 characters into the username or email address fields, causing the application to become unresponsive.",
  "id": "GHSA-chp4-5883-3f2x",
  "modified": "2026-01-15T18:31:30Z",
  "published": "2026-01-15T18:31:30Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47765"
    },
    {
      "type": "WEB",
      "url": "https://www.celestialsoftware.net"
    },
    {
      "type": "WEB",
      "url": "https://www.exploit-db.com/exploits/50510"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/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"
    }
  ]
}

CVE-2021-47765 (GCVE-0-2021-47765)

Vulnerability from cvelistv5 – Published: 2026-01-15 15:52 – Updated: 2026-01-26 15:55

Title

AbsoluteTelnet 11.24 - 'Username' Denial of Service (PoC)

Summary

Severity

6.7 (Medium)


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

5.5 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-01-15 16:47 UTC

CWE

CWE-787 - Out-of-bounds Write

Assigner

VulnCheck mitre root

References

2 references

URL	Tags
https://www.exploit-db.com/exploits/50510	exploit
https://www.celestialsoftware.net/	product

Impacted products

1 product

Vendor	Product	Version
Celestialsoftware	AbsoluteTelnet	Affected: 11.24

Date Public

2021-11-10 00:00

Credits

Yehia Elghaly

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2021-47765",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-15T16:47:29.833009Z",
                "version": "2.0.3"
              },
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          "shortName": "CISA-ADP"
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            }
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            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
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            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
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            "baseScore": 6.7,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
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            "integrityImpact": "NONE",
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            "userInteraction": "NONE",
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            "version": "3.1"
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        },
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      ],
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  "cveMetadata": {
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    "datePublished": "2026-01-15T15:52:08.912Z",
    "dateReserved": "2026-01-14T14:39:44.735Z",
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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.

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.
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.

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.