CVE-2021-22564
Out of bounds Copy in Libjxl in large image groups
For certain valid JPEG XL images with a size slightly larger than an integer number of groups (256x256 pixels) when processing the groups out of order the decoder can perform an out of bounds copy of image pixels from an image buffer in the heap to another. This copy can occur when processing the right or bottom edges of the image, but only when groups are processed in certain order. Groups can be processed out of order in multi-threaded decoding environments with heavy thread load but also with images that contain the groups in an arbitrary order in the file. It is recommended to upgrade past 0.6.0 or patch with https://github.com/libjxl/libjxl/pull/775
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
4.5
Out of bounds Copy in Libjxl in large image groups
For certain valid JPEG XL images with a size slightly larger than an integer number of groups (256x256 pixels) when processing the groups out of order the decoder can perform an out of bounds copy of image pixels from an image buffer in the heap to another. This copy can occur when processing the right or bottom edges of the image, but only when groups are processed in certain order. Groups can be processed out of order in multi-threaded decoding environments with heavy thread load but also with images that contain the groups in an arbitrary order in the file. It is recommended to upgrade past 0.6.0 or patch with https://github.com/libjxl/libjxl/pull/775
- Record
CVE-2021-22564- CVSS 3.1
- 4.5 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-122
- Updated
- 2026-11-02
EUVDEUVD-2021-9704
4.5
For certain valid JPEG XL images with a size slightly larger than an integer number of groups (256x256 pixels) when processing the groups out of order the decoder can perform an out of bounds copy of image pixels from an image buffer in the heap to another. This copy can occur when processing the right or bottom edges of the image, but only when groups are processed in certain order. Groups can be processed out of order in multi-threaded decoding environments with heavy thread load but also with images that contain the groups in an arbitrary order in the file. It is recommended to upgrade past 0.6.0 or patch with https://github.com/libjxl/libjxl/pull/775
- Record
EUVD-2021-9704- CVSS 3.1
- 4.5 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-fj6w-9c57-3287 No score
For certain valid JPEG XL images with a size slightly larger than an integer number of groups ...
For certain valid JPEG XL images with a size slightly larger than an integer number of groups (256x256 pixels) when processing the groups out of order the decoder can perform an out of bounds copy of image pixels from an image buffer in the heap to another. This copy can occur when processing the right or bottom edges of the image, but only when groups are processed in certain order. Groups can be processed out of order in multi-threaded decoding environments with heavy thread load but also with images that contain the groups in an arbitrary order in the file. It is recommended to upgrade past 0.6.0 or patch with https://github.com/libjxl/libjxl/pull/775
- Record
GHSA-fj6w-9c57-3287- Weakness
- CWE-787
- Updated
- 2026-11-02
NVD
4.5
For certain valid JPEG XL images with a size slightly larger than an integer number of groups (256x256 pixels) when processing the groups out of order the decoder can perform an out of bounds copy of image pixels from an image buffer in the heap to another. This copy can occur when processing the right or bottom edges of the image, but only when groups are processed in certain order. Groups can be processed out of order in multi-threaded decoding environments with heavy thread load but also with images that contain the groups in an arbitrary order in the file. It is recommended to upgrade past 0.6.0 or patch with https://github.com/libjxl/libjxl/pull/775
- Record
CVE-2021-22564- CVSS 3.1
- 4.5 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L - CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 2.1 Low
AV:L/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-122, CWE-787
- Updated
- 2026-11-02
OSV
5.5
For certain valid JPEG XL images with a size slightly larger than an integer number of groups (256x256 pixels) when processing the groups out of order the decoder can perform an out of bounds copy of image pixels from an image buffer in the heap to another. This copy can occur when processing the right or bottom edges of the image, but only when groups are processed in certain order. Groups can be processed out of order in multi-threaded decoding environments with heavy thread load but also with images that contain the groups in an arbitrary order in the file. It is recommended to upgrade past 0.6.0 or patch with https://github.com/libjxl/libjxl/pull/775
- Record
CVE-2021-22564- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, products, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-22564 is a medium vulnerability (CVSS 4.5) in Google Libjxl, published November 1, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.31%, the 24th percentile. No source names a fixed version.