Vulnerability-Lookup

GHSA-58P4-4G24-J8VP

Vulnerability from github – Published: 2026-09-21 18:32 – Updated: 2026-09-21 18:32

Details

Telegram Desktop before 6.9.4 allows XSS in the HTML exporter. (The first fixed stable version is 7.0.1.) This occurs in button.text.toUtf8 in export_output_html.cpp. Exploitation cannot occur unless HTML export was used by a victim. However, the exploit payload can be exported if a message were forwarded into a group by a member (it is not necessary for the message author to be a member of a group).

Severity

8.2 (High)


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

8.3 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-94488"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-21T18:17:17Z",
    "severity": "HIGH"
  },
  "details": "Telegram Desktop before 6.9.4 allows XSS in the HTML exporter. (The first fixed stable version is 7.0.1.) This occurs in button.text.toUtf8 in export_output_html.cpp. Exploitation cannot occur unless HTML export was used by a victim. However, the exploit payload can be exported if a message were forwarded into a group by a member (it is not necessary for the message author to be a member of a group).",
  "id": "GHSA-58p4-4g24-j8vp",
  "modified": "2026-09-21T18:32:09Z",
  "published": "2026-09-21T18:32:09Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-94488"
    },
    {
      "type": "WEB",
      "url": "https://github.com/telegramdesktop/tdesktop/commit/52c779bffa8dde3c5c09826add2607328fae0924"
    },
    {
      "type": "WEB",
      "url": "https://github.com/telegramdesktop/tdesktop/commit/8457d13aa795fadf99c955d2a04f00ebc3c59df9"
    },
    {
      "type": "WEB",
      "url": "https://expatch.com/writeups/telegram-html-export-xss.html"
    },
    {
      "type": "WEB",
      "url": "https://github.com/telegramdesktop/tdesktop/blob/v6.9.3/Telegram/SourceFiles/export/output/export_output_html.cpp"
    },
    {
      "type": "WEB",
      "url": "https://github.com/telegramdesktop/tdesktop/releases/tag/v6.9.4"
    },
    {
      "type": "WEB",
      "url": "https://thehackernews.com/2026/09/telegram-desktop-flaw-lets-hidden.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/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-2026-94488 (GCVE-0-2026-94488)

Vulnerability from cvelistv5 – Published: 2026-09-21 17:29 – Updated: 2026-09-21 17:51

Summary

Severity

8.3 (High)


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

8.2 (High)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-21 17:51 UTC

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Assigner

mitre mitre root

References

6 references

URL	Tags
https://github.com/telegramdesktop/tdesktop/commi…	patch
https://github.com/telegramdesktop/tdesktop/commi…	related
https://github.com/telegramdesktop/tdesktop/relea…	release-notes
https://github.com/telegramdesktop/tdesktop/blob/…	related
https://expatch.com/writeups/telegram-html-export…	third-party-advisorytechnical-descriptionexploit
https://thehackernews.com/2026/09/telegram-deskto…	media-coverage

Impacted products

1 product

Vendor	Product	Version
Telegram	Telegram Desktop	Affected: 4.15.1 , < 6.9.4 (semver) cpe:2.3:a:telegram:telegram_desktop::::::::

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JSON

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                "id": "CVE-2026-94488",
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                  },
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                  }
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                "role": "CISA Coordinator",
                "timestamp": "2026-09-21T17:51:08.525648Z",
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            }
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            "Recovery": "NOT_DEFINED",
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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.

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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GHSA-58P4-4G24-J8VP

CVE-2026-94488 (GCVE-0-2026-94488)

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