ImageSharp: BigTIFF IFD count can keep a decoder thread in a non-progressing loop

Summary SixLabors.ImageSharp 4.1.1 can spend an attacker-controlled duration decoding a small malformed BigTIFF. The BigTIFF IFD entry-count field is 64-bit. The reader iterates once per declared entry, but when fewer than 20 bytes remain for an entry, the entry read returns without advancing. A...

GHSA-WMXV-XPHR-5C9G ImageSharp: BigTIFF IFD count can keep a decoder thread in a non-progressing loop

Summary SixLabors.ImageSharp 4.1.1 can spend an attacker-controlled duration decoding a small malformed BigTIFF. The BigTIFF IFD entry-count field is 64-bit. The reader iterates once per declared entry, but when fewer than 20 bytes remain for an entry, the entry read returns without advancing. A...

CVE-2026-106116 ImageSharp: BigTIFF IFD count can keep a decoder thread in a non-progressing loop

ImageSharp is a 2D graphics library. From 2.0.0 until 4.1.2, ExifReader.ReadValues64 trusts the 64-bit BigTIFF IFD entry count and iterates once per declared entry. When fewer than 20 bytes remain, ExifReader.ReadValue64 returns without advancing the stream or terminating the outer loop, so a sma...

CVE-2026-106116 ImageSharp: BigTIFF IFD count can keep a decoder thread in a non-progressing loop

ImageSharp is a 2D graphics library. From 2.0.0 until 4.1.2, ExifReader.ReadValues64 trusts the 64-bit BigTIFF IFD entry count and iterates once per declared entry. When fewer than 20 bytes remain, ExifReader.ReadValue64 returns without advancing the stream or terminating the outer loop, so a sma...

CVE-2026-106116 ImageSharp: BigTIFF IFD count can keep a decoder thread in a non-progressing loop

ImageSharp is a 2D graphics library. From 2.0.0 until 4.1.2, ExifReader.ReadValues64 trusts the 64-bit BigTIFF IFD entry count and iterates once per declared entry. When fewer than 20 bytes remain, ExifReader.ReadValue64 returns without advancing the stream or terminating the outer loop, so a sma...

CVE-2026-106116

The ImageSharp 2D graphics library versions 2.0.0 through 4.1.2 are vulnerable to a non-progressing loop when processing malformed BigTIFF files. The root cause is located in ExifReader.ReadValues64 , which trusts the 64-bit BigTIFF IFD entry count and iterates accordingly. When fewer than 20 byt...