CVE-2026-44638

>= 1.0.0 and < 1.8.7-r2

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. From to 1.8.7-r1, a wrong NULL check after an allo

2.5LOW

CVE-2026-44637

>= 0.11.0 and < 1.8.7-r2

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. From to 1.8.7-r1, a signed integer overflow in the

7.1HIGH

CVE-2026-44636

>= 1.4.4 and < 1.8.7-r2

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. From to 1.8.7-r1, signed integer overflow in sixel

7.4HIGH

CVE-2026-33023

<= 1.8.7

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. In versions 1.8.7 and prior, when built with the --

7.8HIGH

CVE-2026-33021

< 1.8.7-r1

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. Versions 1.8.7 and prior contain a use-after-free v

7.3HIGH

CVE-2026-33020

< 1.8.7-r1

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. Versions 1.8.7 and prior contain an integer overflo

7.1HIGH

CVE-2026-33019

< 1.8.7-r1

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. Versions 1.8.7 and prior contain an integer overflo

7.1HIGH

CVE-2026-33018

< 1.8.7-r1

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. Versions 1.8.7 and prior contain a Use-After-Free v

7.0HIGH

CVE-2025-61146

< 1.8.7

saitoha libsixel until v1.8.7 was discovered to contain a memory leak via the component malloc_stub.c.

4.0MEDIUM

CVE-2025-9300

< 1.8.7

A vulnerability was found in saitoha libsixel up to 1.10.3. Affected by this issue is the function sixel_debug_print_palette of th

5.3MEDIUM

CVE-2022-29978

all versions

There is a floating point exception error in sixel_encoder_do_resize, encoder.c:633 in libsixel img2sixel 1.8.6. Remote attackers

6.5MEDIUM

CVE-2022-29977

all versions

There is an assertion failure error in stbi__jpeg_huff_decode, stb_image.h:1894 in libsixel img2sixel 1.8.6. Remote attackers coul

6.5MEDIUM

CVE-2021-40656

< 1.10.0

libsixel before 1.10 is vulnerable to Buffer Overflow in libsixel/src/quant.c:867.

8.8HIGH

CVE-2022-27046

all versions

libsixel 1.8.6 suffers from a Heap Use After Free vulnerability in libsixel/src/dither.c:388.

8.8HIGH

CVE-2022-27044

all versions

libsixel 1.8.6 is affected by Buffer Overflow in libsixel/src/quant.c:876.

8.8HIGH

CVE-2021-41715

all versions

libsixel 1.10.0 is vulnerable to Use after free in libsixel/src/dither.c:379.

8.8HIGH

CVE-2022-27938

< 1.8.7

stb_image.h (aka the stb image loader) 2.19, as used in libsixel and other products, has a reachable assertion in stbi__create_png

5.5MEDIUM

CVE-2021-46700

all versions

In libsixel 1.8.6, sixel_encoder_output_without_macro (called from sixel_encoder_encode_frame in encoder.c) has a double free.

6.5MEDIUM

CVE-2021-45340

<= 1.10.3

In Libsixel prior to and including v1.10.3, a NULL pointer dereference in the stb_image.h component of libsixel allows attackers t

6.5MEDIUM

CVE-2020-21548

all versions

Libsixel 1.8.3 contains a heap-based buffer overflow in the sixel_encode_highcolor function in tosixel.c.

8.8HIGH

CVE-2020-21547

all versions

Libsixel 1.8.2 contains a heap-based buffer overflow in the dither_func_fs function in tosixel.c.

8.8HIGH

CVE-2020-21050

< 1.8.3

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

6.5MEDIUM

CVE-2020-21049

< 1.8.5

An invalid read in the stb_image.h component of libsixel prior to v1.8.5 allows attackers to cause a denial of service (DOS) via a

6.5MEDIUM

CVE-2020-21048

< 1.8.4

An issue in the dither.c component of libsixel prior to v1.8.4 allows attackers to cause a denial of service (DOS) via a crafted P

6.5MEDIUM

CVE-2020-21677

all versions

A heap-based buffer overflow in the sixel_encoder_output_without_macro function in encoder.c of Libsixel 1.8.4 allows attackers to

6.5MEDIUM

CVE-2020-36120

all versions

Buffer Overflow in the "sixel_encoder_encode_bytes" function of Libsixel v1.8.6 allows attackers to cause a Denial of Service (DoS

7.5HIGH

CVE-2020-19668

all versions

Unverified indexs into the array lead to out of bound access in the gif_out_code function in fromgif.c in libsixel 1.8.6.

6.5MEDIUM

CVE-2020-11721

all versions

load_png in loader.c in libsixel.a in libsixel 1.8.6 has an uninitialized pointer leading to an invalid call to free, which can ca

6.5MEDIUM

CVE-2019-20205

all versions

libsixel 1.8.4 has an integer overflow in sixel_frame_resize in frame.c.

8.8HIGH

CVE-2019-20140

all versions

An issue was discovered in libsixel 1.8.4. There is a heap-based buffer overflow in the function gif_out_code at fromgif.c.

8.8HIGH

CVE-2019-20094

all versions

An issue was discovered in libsixel 1.8.4. There is a heap-based buffer overflow in the function gif_init_frame at fromgif.c.

8.8HIGH

CVE-2019-20024

< 1.8.4

A heap-based buffer overflow was discovered in image_buffer_resize in fromsixel.c in libsixel before 1.8.4.

6.5MEDIUM

CVE-2019-20023

< 1.8.4

A memory leak was discovered in image_buffer_resize in fromsixel.c in libsixel 1.8.4.

6.5MEDIUM

CVE-2019-20022

< 1.8.3

An invalid memory address dereference was discovered in load_pnm in frompnm.c in libsixel before 1.8.3.

6.5MEDIUM

CVE-2019-19778

all versions

An issue was discovered in libsixel 1.8.2. There is a heap-based buffer over-read in the function load_sixel at loader.c.

8.8HIGH

CVE-2019-19777

all versions

stb_image.h (aka the stb image loader) 2.23, as used in libsixel and other products, has a heap-based buffer over-read in stbi__lo

8.8HIGH

CVE-2019-19638

all versions

An issue was discovered in libsixel 1.8.2. There is a heap-based buffer overflow in the function load_pnm at frompnm.c, due to an

9.8CRITICAL

CVE-2019-19637

all versions

An issue was discovered in libsixel 1.8.2. There is an integer overflow in the function sixel_decode_raw_impl at fromsixel.c.

9.8CRITICAL

CVE-2019-19636

all versions

An issue was discovered in libsixel 1.8.2. There is an integer overflow in the function sixel_encode_body at tosixel.c.

9.8CRITICAL

CVE-2019-19635

all versions

An issue was discovered in libsixel 1.8.2. There is a heap-based buffer overflow in the function sixel_decode_raw_impl at fromsixe

9.8CRITICAL

CVE-2019-11024

all versions

The load_pnm function in frompnm.c in libsixel.a in libsixel 1.8.2 has infinite recursion.

5.5MEDIUM

CVE-2019-3574

all versions

In libsixel v1.8.2, there is a heap-based buffer over-read in the function load_jpeg() in the file loader.c, as demonstrated by im

7.8HIGH

CVE-2019-3573

all versions

In libsixel v1.8.2, there is an infinite loop in the function sixel_decode_raw_impl() in the file fromsixel.c, as demonstrated by

5.5MEDIUM

CVE-2018-19763

all versions

There is a heap-based buffer over-read at writer.c (function: write_png_to_file) in libsixel 1.8.2 that will cause a denial of ser

5.5MEDIUM

CVE-2018-19762

all versions

There is a heap-based buffer overflow at fromsixel.c (function: image_buffer_resize) in libsixel 1.8.2 that will cause a denial of

7.8HIGH

CVE-2018-19761

all versions

There is an illegal address access at fromsixel.c (function: sixel_decode_raw_impl) in libsixel 1.8.2 that will cause a denial of

5.5MEDIUM

CVE-2018-19759

all versions

There is a heap-based buffer over-read at stb_image_write.h (function: stbi_write_png_to_mem) in libsixel 1.8.2 that will cause a

5.5MEDIUM

CVE-2018-19757

all versions

There is a NULL pointer dereference at function sixel_helper_set_additional_message (status.c) in libsixel 1.8.2 that will cause a

6.5MEDIUM

CVE-2018-19756

all versions

There is a heap-based buffer over-read at stb_image.h (function: stbi__tga_load) in libsixel 1.8.2 that will cause a denial of ser

5.5MEDIUM

CVE-2018-14073

all versions

libsixel 1.8.1 has a memory leak in sixel_allocator_new in allocator.c.

7.5HIGH

CVE-2018-14072

all versions

libsixel 1.8.1 has a memory leak in sixel_decoder_decode in decoder.c, image_buffer_resize in fromsixel.c, and sixel_decode_raw in

7.5HIGH