High severity · published Dec 24, 2018
CVE-2018-20436
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…
8.1
CVSS
1.6%
EPSS
No
On KEV
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 vector
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.6% · higher than 75% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TE
Telegram · Telegram
4.9.1 · source: NVD
WE
Web · Telegram
0.7.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-20436
CVE.org
https://www.cve.org/CVERecord?id=CVE-2018-20436
Exploit
https://misteralfa-hack.blogspot.com/2018/12/abusando-de-telegram-para-conseguir-una.html
Exploit
https://misteralfa-hack.blogspot.com/2018/12/telegram-siempre-in-middle.html
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