Telegram 4.9.1 on Android Secret Chat server-side request forgery

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.8$5k-$25k0.00

Summaryinfo

A vulnerability classified as critical was found in Telegram 4.9.1 on Android. Affected is an unknown function of the component Secret Chat. Executing a manipulation can lead to server-side request forgery. This vulnerability is registered as CVE-2018-20436. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability has been found in Telegram 4.9.1 on Android (Android App Software) and classified as critical. This vulnerability affects an unknown function of the component Secret Chat. The manipulation with an unknown input leads to a server-side request forgery vulnerability. The CWE definition for the vulnerability is CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The bug was discovered 12/02/2018. The weakness was published 12/24/2018 (Website). The advisory is shared for download at misteralfa-hack.blogspot.com. This vulnerability was named CVE-2018-20436 since 12/24/2018. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 08/05/2024).

The vulnerability was handled as a non-public zero-day exploit for at least 22 days. During that time the estimated underground price was around $5k-$25k.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.8

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.1
NVD Vector: 🔍

CNA Base Score: 8.1
CNA Vector: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Server-side request forgery
CWE: CWE-918
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/02/2018 🔍
12/24/2018 +22 days 🔍
12/24/2018 +0 days 🔍
12/24/2018 +0 days 🔍
12/25/2018 +1 days 🔍
08/05/2024 +2050 days 🔍

Sourcesinfo

Advisory: misteralfa-hack.blogspot.com
Status: Not defined

CVE: CVE-2018-20436 (🔍)
GCVE (CVE): GCVE-0-2018-20436
GCVE (VulDB): GCVE-100-128380
scip Labs: https://www.scip.ch/en/?labs.20130704

Entryinfo

Created: 12/25/2018 10:36
Updated: 08/05/2024 21:45
Changes: 12/25/2018 10:36 (58), 04/24/2020 08:45 (2), 08/05/2024 21:45 (28)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Want to know what is going to be exploited?

We predict KEV entries!