CVE-2021-30496Network attack vector

Authenticated message paste crash

Published Apr 20, 2021 · Updated Aug 3, 2024

Denial of service in Telegram 7.6.2 for iOS allows remote authenticated users to crash the app by pasting attacker-supplied messages. Public records identify MtProtoKitFramework as the crash locus but do not disclose the parsing operation that fails. The victim must paste the crafted text into a channel or group, and Telegram disputes that the behavior constitutes a vulnerability.

CVSS severity5.7
Medium
EPSS probability1.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Telegram 7.6.2 for iOS allows remote authenticated users to crash the app by pasting attacker-supplied messages. Public records identify MtProtoKitFramework as the crash locus but do not disclose the parsing operation that fails. The victim must paste the crafted text into a channel or group, and Telegram disputes that the behavior constitutes a vulnerability.

The record

CVE
CVE-2021-30496
Published
Apr 20, 2021
Updated
Aug 3, 2024
Vendor
Telegram
Product
Telegram
Classifications
CWE-121, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 20, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=7.6.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Telegram · Telegramversion=7.6.2

Published CVSS scores

5.7CISA ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-121Stack-based Buffer Overflow
T1499.004Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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