Is ujson safe to use?

ujson has 2 known vulnerabilities on the latest version (5.12.1). DepScope rates its health at 86/100 (low risk).

What is the latest version of ujson?

The latest version of ujson is 5.12.1, released 2026-05-05.

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: 5.12.1 (2026-05-05).

What are alternatives to ujson?

Popular alternatives to ujson in PyPI include: boto3, packaging, urllib3, certifi, requests.

What license does ujson use?

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

ujson

pypiv5.12.1

Ultra fast JSON encoder and decoder for Python

License BSD-3-Clause AND TCLpermissive41 versions1 maintainers0 deps7,771,508 weekly dl

ultrajson/ultrajson

/ 100

Health

safe to use

[email protected] is safe to use (health: 86/100)

Update to >= 5525f8c9ef8bb879dadd0eb942d524827d1b0362 to fix known vulnerabilities

Health breakdown0 – 100

25/25

maintenance

17/20

popularity

25/25

security

12/15

maturity

7/15

community

0/15

popularity_floor

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

Maintainer trust

Active maintainers (3m)

4

Contributors (12m)

9

Primary author dominance

56%

GitHub stars

4,484

recent ownership change suspected

Quality signals

Download trend

stable(0%)

Publish security

API token

Health History

Dependency Tree

License Audit

API access

Get this data programmatically — free, no authentication.

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

ujson

pypiv5.12.1

Ultra fast JSON encoder and decoder for Python

License BSD-3-Clause AND TCLpermissive41 versions1 maintainers0 deps7,771,508 weekly dl

ultrajson/ultrajson

/ 100

Health

safe to use

[email protected] is safe to use (health: 86/100)

Update to >= 5525f8c9ef8bb879dadd0eb942d524827d1b0362 to fix known vulnerabilities

Health breakdown0 – 100

25/25

maintenance

17/20

popularity

25/25

security

12/15

maturity

7/15

community

0/15

popularity_floor

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

Maintainer trust

Active maintainers (3m)

4

Contributors (12m)

9

Primary author dominance

56%

GitHub stars

4,484

recent ownership change suspected

Quality signals

Download trend

stable(0%)

Publish security

API token

Health History

Dependency Tree

License Audit

API access

Get this data programmatically — free, no authentication.

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