CVE-2026-94488Public exploitHinoki check available

Stored XSS via unescaped inline-button text

Published Sep 21, 2026 · Updated Sep 21, 2026

Stored XSS in Telegram Desktop 4.15.1 through 6.9.3 allows attackers to read or alter opened HTML chat exports. HtmlWriter::Wrap::pushMessage writes button.text.toUtf8() into export_output_html.cpp output without SerializeString HTML escaping, so inline-keyboard markup becomes executable browser content. Exploitation requires a victim to export an affected chat to HTML and open it; a forwarded bot message can seed the payload without the bot joining the group.

CVSS severity8.3
High
EPSS probability0.14%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Stored XSS in Telegram Desktop 4.15.1 through 6.9.3 allows attackers to read or alter opened HTML chat exports. HtmlWriter::Wrap::pushMessage writes button.text.toUtf8() into export_output_html.cpp output without SerializeString HTML escaping, so inline-keyboard markup becomes executable browser content. Exploitation requires a victim to export an affected chat to HTML and open it; a forwarded bot message can seed the payload without the bot joining the group.

The record

CVE
CVE-2026-94488
Published
Sep 21, 2026
Updated
Sep 21, 2026
Vendor
Telegram
Product
Telegram Desktop
Classifications
CWE-79, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.15.1 <6.9.4

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Telegram · Telegram Desktopversion=4.15.1 <6.9.4

Published CVSS scores

8.3MITRECVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
8.2MITRECVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.002Malicious File

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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