8.2
HIGH CVSS 4.0
CVE-2026-109426
Telegram-Stremio 5.1.0 Insecure Session Storage via encode_string
Description

Telegram-Stremio through 5.1.0 contains an insecure storage vulnerability that allows attackers with access to the MongoDB database, backups, or logs to recover the operator's authenticated Telegram session string, which is protected only by a keyless, reversible encoding transform rather than actual encryption. Attackers can round-trip the stored value through the repository's own decode_string function with no secret key to obtain a fully authenticated Telegram session, granting complete control of the operator's Telegram account even when two-step verification is enabled.

INFO

Published Date :

Oct. 12, 2026, 9:17 p.m.

Last Modified :

Oct. 12, 2026, 9:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-109426 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH MITRE-CVE
CVSS 3.1 HIGH [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Update Telegram-Stremio to a version that implements proper encryption for session strings.
  • Update Telegram-Stremio to the latest version.
  • Ensure session strings are protected with strong encryption.
  • Avoid reversible encoding for sensitive data.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-109426.

URL Resource
https://gist.github.com/mansurmavlankulov/489554cad7b38e07b9651c217f00fffb
https://www.vulncheck.com/advisories/telegram-stremio-insecure-session-storage-via-encode-string
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-109426 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-109426 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-109426 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-109426 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Oct. 12, 2026

    Action Type Old Value New Value
    Added Description Telegram-Stremio through 5.1.0 contains an insecure storage vulnerability that allows attackers with access to the MongoDB database, backups, or logs to recover the operator's authenticated Telegram session string, which is protected only by a keyless, reversible encoding transform rather than actual encryption. Attackers can round-trip the stored value through the repository's own decode_string function with no secret key to obtain a fully authenticated Telegram session, granting complete control of the operator's Telegram account even when two-step verification is enabled.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/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
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
    Added CWE CWE-312
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/109xxx/CVE-2026-109426.json">CVE-2026-109426</a>
    Added Reference https://gist.github.com/mansurmavlankulov/489554cad7b38e07b9651c217f00fffb
    Added Reference https://www.vulncheck.com/advisories/telegram-stremio-insecure-session-storage-via-encode-string
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.