CVE-2020-21677: A heap-based buffer overflow in the sixel_encoder_output_without_macro function in encoder.c of Libsixel 1.8.4 allows attackers to cause a denial of service…

PriorityP425medium6.5CVSS 3.1

AVNACLPRNUIRSUCNINAH

EPSS

0.90%

56.1th percentile

A heap-based buffer overflow in the sixel_encoder_output_without_macro function in encoder.c of Libsixel 1.8.4 allows attackers to cause a denial of service (DOS) via converting a crafted PNG file into Sixel format.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
debian	libsixel	< libsixel 1.8.6-1 (bookworm)	libsixel 1.8.6-1 (bookworm)
libsixel_project	libsixel	>= 0 < 1.8.6-1	1.8.6-1
libsixel_project	libsixel	>= 0 < 1.8.6-1	1.8.6-1
libsixel_project	libsixel	>= 0 < 1.8.6-1	1.8.6-1
libsixel_project	libsixel	>= 0 < 1.8.6-1	1.8.6-1
saitoha	libsixel	—	—

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:N/A:P

osv6.5MEDIUM

vendor_debian6.5MEDIUM

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