Is ujson safe to use?

ujson has 2 known vulnerabilities on the latest version (6.0.0). DepScope rates its health at 69/100 (moderate risk).

What is the latest version of ujson?

The latest version of ujson is 6.0.0, released 2026-09-04.

Does ujson have known vulnerabilities?

Yes. ujson has 2 known vulnerabilities. See depscope.dev/pkg/pypi/ujson for details.

No, ujson is actively maintained. Latest release: 6.0.0 (2026-09-04).

What are alternatives to ujson?

Popular alternatives to ujson in PyPI include: typing_extensions, six, annotated_types, typing_inspection, mdurl.

What license does ujson use?

ujson is licensed under BSD-3-Clause AND TCL.

ujson

pypiv6.0.0

Ultra fast JSON encoder and decoder for Python

License BSD-3-Clause AND TCLpermissive43 versions1 maintainers0 deps

ultrajson/ultrajson

/ 100

Health

use with caution

[email protected] low health (69/100) — consider alternatives

Update to >= 5525f8c9ef8bb879dadd0eb942d524827d1b0362 to fix known vulnerabilities

Moderate health score (69/100) — verify manually

Health breakdown0 – 100

25/25

maintenance

0/20

popularity

25/25

security

12/15

maturity

7/15

community

Vulnerabilities

2 low

Advisories (2)

Severity	ID	Summary	Fixed in
unknown	OSV-2021-1809	Heap-buffer-overflow in ujson.cpython-38-x86_64-linux-gnu.so	550ba4d77294e61597a5259d00769c61281e0042
unknown	OSV-2021-955	Stack-buffer-overflow in Buffer_AppendIndentUnchecked	5525f8c9ef8bb879dadd0eb942d524827d1b0362

Health History

Dependency Tree

License Audit

API access

Get this data programmatically — free, no authentication.

curl https://depscope.dev/api/check/pypi/ujson

ujson

pypiv6.0.0

Ultra fast JSON encoder and decoder for Python

License BSD-3-Clause AND TCLpermissive43 versions1 maintainers0 deps

ultrajson/ultrajson

/ 100

Health

use with caution

[email protected] low health (69/100) — consider alternatives

Update to >= 5525f8c9ef8bb879dadd0eb942d524827d1b0362 to fix known vulnerabilities

Moderate health score (69/100) — verify manually

Health breakdown0 – 100

25/25

maintenance

0/20

popularity

25/25

security

12/15

maturity

7/15

community

Vulnerabilities

2 low

Advisories (2)

Severity	ID	Summary	Fixed in
unknown	OSV-2021-1809	Heap-buffer-overflow in ujson.cpython-38-x86_64-linux-gnu.so	550ba4d77294e61597a5259d00769c61281e0042
unknown	OSV-2021-955	Stack-buffer-overflow in Buffer_AppendIndentUnchecked	5525f8c9ef8bb879dadd0eb942d524827d1b0362

Health History

Dependency Tree

License Audit

API access

Get this data programmatically — free, no authentication.

curl https://depscope.dev/api/check/pypi/ujson