CVE-2018-20436
In addition, it can be interpreted as an SSRF issue.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.55%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
The "secret chat" feature in Telegram 4.9.1 for Android has a "side channel" in which Telegram servers send GET requests for URLs typed while composing a chat message, before that chat message is sent. There are also GET requests to other URLs on the same web server. This also affects one or more other Telegram products, such as Telegram Web-version 0.7.0. In addition, it can be interpreted as an SSRF issue. NOTE: a third party has reported that potentially unwanted behavior is caused by misconfiguration of the "Secret chats > Preview links" setting
- CVSS 3.0
- 8.1 HIGHCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.55% probability · 75th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-918
- Affected
- telegram/telegram · telegram/web
- Source
- cve@mitre.org
EPSS 1.6% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://misteralfa-hack.blogspot.com/2018/12/abusando-de-telegram-para-conseguir-una.htmlExploit, Third Party Advisory
- https://misteralfa-hack.blogspot.com/2018/12/telegram-siempre-in-middle.htmlExploit, Third Party Advisory
- https://misteralfa-hack.blogspot.com/2018/12/abusando-de-telegram-para-conseguir-una.htmlExploit, Third Party Advisory
- https://misteralfa-hack.blogspot.com/2018/12/telegram-siempre-in-middle.htmlExploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.