CVE-2026-94488

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.13% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 3.2% of scored records. A rank, not a probability.

NVD base score

8.3 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

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

NVD analysis status

Awaiting Analysis. NVD last modified this record on 2026-09-22.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-09-21 17:29Z1 MO AGO

Last updated

2026-09-21 17:51Z1 MO AGO

Reserved

2026-09-21

Assigning CNA

mitre

Record state

PUBLISHED

Severity

High (CVSS 8.3)

CNA CVSS vector

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

Weaknesses

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

Data version

5.2

Document digest

374049b717f9eee73f12a5d280cd8880b1938f65e9fbf69eeecadd16bcd8c93c

• github.comtdesktop commit 8457d13a - Fix escaping in HTML export of keyboardshttps://github.com/telegramdesktop/tdesktop/commit/8457d13aa795fadf99c955d2a04f00ebc3c59df9patch
• github.comtdesktop commit 52c779bf - Added support of inline markup reply to HTML export (introduces the issue)https://github.com/telegramdesktop/tdesktop/commit/52c779bffa8dde3c5c09826add2607328fae0924related
• github.comTelegram Desktop v6.9.4 - first release containing the fixhttps://github.com/telegramdesktop/tdesktop/releases/tag/v6.9.4release-notes
• github.comVulnerable export_output_html.cpp as shipped in v6.9.3https://github.com/telegramdesktop/tdesktop/blob/v6.9.3/Telegram/SourceFiles/export/output/export_output_html.cpprelated
• expatch.comExpatch LLC technical write-uphttps://expatch.com/writeups/telegram-html-export-xss.htmlthird-party-advisorytechnical-descriptionexploit
• thehackernews.comhttps://thehackernews.com/2026/09/telegram-desktop-flaw-lets-hidden.htmlmedia-coverage