libsixel up to 1.8.2 fromgif.c gif_process_raster stack-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability was found in libsixel up to 1.8.2. It has been classified as critical. Affected is the function gif_process_raster of the file fromgif.c. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-121. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Libsixel prior to v1.8.3 contains a stack buffer overflow in the function gif_process_raster at fromgif.c.

The weakness was presented 09/15/2021 as 7808a06b88c11dbc502318cdd51fa374f8cd47ee. The advisory is shared for download at This vulnerability is traded as CVE-2020-21050 since 08/13/2020. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available.

Upgrading to version 1.8.3 eliminates this vulnerability. The upgrade is hosted for download at Applying the patch 7808a06b88c11dbc502318cdd51fa374f8cd47ee is able to eliminate this problem. The bugfix is ready for download at The best possible mitigation is suggested to be upgrading to the latest version.



CPE 2.3infoedit

CPE 2.2infoedit


VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍



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


Class: Memory corruption
CWE: CWE-121
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfoedit

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


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libsixel 1.8.3
Patch: 7808a06b88c11dbc502318cdd51fa374f8cd47ee


08/13/2020 CVE assigned
09/15/2021 +398 days Advisory disclosed
09/15/2021 +0 days VulDB entry created
09/17/2021 +2 days VulDB last update


Advisory: 7808a06b88c11dbc502318cdd51fa374f8cd47ee
Status: Confirmed

CVE: CVE-2020-21050 (🔒)


Created: 09/15/2021 03:21 AM
Updated: 09/17/2021 02:50 PM
Changes: (1) source_cve_nvd_summary
Complete: 🔍


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