SSRF in Telegram
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 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
Vulnerability class: SSRF (Server-Side Request Forgery)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.016 (74.2th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 74th percentile — 74.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.016 · newest: 0.016 · change: 0.000
Affected products
- Telegram — versions 4.9.1
- Telegram Web — versions 0.7.0
Weakness classification (CWE)
References
- misteralfa-hack.blogspot.com/2018/12/abusando-de-telegram-para-conseguir-una.ht… (Exploit, Third Party Advisory)
- misteralfa-hack.blogspot.com/2018/12/telegram-siempre-in-middle.html (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2018-20436?
- CVE-2018-20436 is a high-severity vulnerability in Telegram, classified under Server-Side Request Forgery (SSRF). CVSS score: 8.1/10. Published 2018-12-24.
- How severe is CVE-2018-20436?
- High severity. CVSS v3 base score is 8.1 out of 10.