MEDIUM
CVE-2021-31317
CWE-843Published: May 18, 2021· Updated: Jun 17, 2026
5.5
CVSS v3.1
Official Description
Telegram Android <7.1.0 (2090), Telegram iOS <7.1, and Telegram macOS <7.1 are affected by a Type Confusion in the VDasher constructor of their custom fork of the rlottie library. A remote attacker might be able to access Telegram's heap memory out-of-bounds on a victim device via a malicious animated sticker.
Technical Analysis
CVE-2021-31317 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.
A successful exploit results in complete confidentiality breach (data exposure), with a CVSS base score of 5.5.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.None
User InteractionRequired
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityNone
AvailabilityNone
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Affected Vendors & Products
telegram1 product(s)
telegram
Source: NVD CPE · 1 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (4)
→
https://www.shielder.it/advisories/telegram-rlottie-vdasher-vdasher-type-confusion/Exploit · Third Party Advisory
→
https://www.shielder.it/blog/2021/02/hunting-for-bugs-in-telegrams-animated-stickers-remote-attack-surface/Exploit · Third Party Advisory
→
https://www.shielder.it/advisories/telegram-rlottie-vdasher-vdasher-type-confusion/Exploit · Third Party Advisory
→
https://www.shielder.it/blog/2021/02/hunting-for-bugs-in-telegrams-animated-stickers-remote-attack-surface/Exploit · Third Party Advisory
Quick Facts
CVE IDCVE-2021-31317
CVSS Score5.5 / 10
SeverityMEDIUM
WeaknessCWE-843
CISA KEVNo
Affected1 vendor(s)
PublishedMay 18, 2021
Related CVEs (CWE-843)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-31317 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.