CVE-2021-3538: Weak RNG

Published Apr 28, 2021
·
Updated

CVE Description for go.uuid A flaw was found in github.com/satori/go.uuid in versions from commit 0ef6afb2f6cdd6cdaeee3885a95099c63f18fc8c to d91630c8510268e75203009fe7daf2b8e1d60c45. Due to insecure randomness in the g.rand.Read function the generated UUIDs are predictable for an attacker.

Update on 19 September 2024 -- This vulnerability never existed in sif

The official NIST CVE-2021-3538 record says:

> A flaw was found in github.com/satori/go.uuid in versions from commit 0ef6afb2f6cdd6cdaeee3885a95099c63f18fc8c to d91630c8510268e75203009fe7daf2b8e1d60c45.

That commit and that fix were never in a tagged release of satori/go.uuid, and prior to this announcement sif had used the last tag, 1.2.0. The NIST record says version 1.2.0 was vulnerable, but that's not true. So sif was never vulnerable to this. Also, beginning with version 2.0.0, sif does not use satori/go.uuid anymore.

This update was made in response to issue #243 which has more details.

The original, incorrect sif vulnerability description is below.

-------------

Impact

The siftool new command produces predictable UUID identifiers due to insecure randomness in the version of the github.com/satori/go.uuid module used as a dependency.

Patches

A patch is available in version >= v1.2.2 of the module. Users are encouraged to upgrade.

Fixed by https://github.com/hpcng/sif/pull/90

Workarounds

Users passing CreateInfo struct should ensure the ID field is generated using a version of github.com/satori/go.uuid that is not vulnerable to this issue. Unfortunately, the latest tagged release is vulnerable to this issue. One way to obtain a non-vulnerable version is:

go get -u github.com/satori/go.uuid@v1.2.1-0.20180404165556-75cca531ea76

References

https://github.com/satori/go.uuid/issues/73

For more information

If you have any questions or comments about this advisory:

Open an issue in https://github.com/hpcng/sif/issues

Other sources

github.com/satori/go.uuid is a provides pure Go implementation of Universally Unique Identifier (UUID).

Affected versions of this package are vulnerable to Insecure Randomness producing predictable UUID identifiers due to the limited number of bytes read when using the g.rand.Read function.

References:

https://snyk.io/vuln/SNYK-GOLANG-GITHUBCOMSATORIGOUUID-72488 https://github.com/satori/go.uuid/issues/73 https://github.com/satori/go.uuid/commit/d91630c8510268e75203009fe7daf2b8e1d60c45

Red Hat

Affected Software

4 affected componentsFixes available
go/github.com/satori/go.uuid>=1.2.1-0.20180103161547-0ef6afb2f6cd<1.2.1-0.20180404165556-75cca531ea76
1.2.1-0.20180404165556-75cca531ea76
Go.uuid Project Go.uuid<1.2
satori Uuid Go
IBM Edge Application Manager<=4.5

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade go/github.com/satori/go.uuid to a version that resolves this vulnerability.

    Fixed in 1.2.1-0.20180404165556-75cca531ea76
  2. Upgrade

    Upgrade github.com/satori/go.uuid to a version that resolves this vulnerability.

    Fixed in v1.2.2
  3. Upgrade

    Upgrade github.com/satori/go.uuid to a version that resolves this vulnerability.

    Fixed in v1.2.1-0.20180404165556-75cca531ea76Patch SNYK-GOLANG-GITHUBCOMSATORIGOUUID-72488
  4. Operational

    If using siftool new (or any code that sets CreateInfo.ID), ensure the UUID ID is generated using a non-vulnerable version of github.com/satori/go.uuid (i.e., a version not in the vulnerable commit range 0ef6afb2f6cdd6cdaeee3885a95099c63f18fc8c to d91630c8510268e75203009fe7daf2b8e1d60c45).

Event History

Apr 28, 2021
Data Sourced
via Red Hat·03:58 AM
DescriptionSeverityAffected Software
Jun 2, 2021
CVE Published
via MITRE·01:22 PM
Data Sourced
via MITRE·01:22 PM
DescriptionWeakness
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected Software
Feb 7, 2023
Advisory Published
via GitHub·10:57 PM
Aug 20, 2025
Data Sourced
via IBM·12:00 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2021-3538?

CVE-2021-3538 has been rated as a moderate severity vulnerability due to its potential impact on UUID predictability.

2

How do I fix CVE-2021-3538?

To fix CVE-2021-3538, update to a version of github.com/satori/go.uuid after 1.2.1-0.20180404165556-75cca531ea76.

3

What is the main issue with CVE-2021-3538?

The main issue with CVE-2021-3538 is that it involves insecure randomness in UUID generation, making the UUIDs predictable for attackers.

4

Which versions are affected by CVE-2021-3538?

CVE-2021-3538 affects github.com/satori/go.uuid from version 1.2.1-0.20180103161547-0ef6afb2f6cd up to 1.2.1-0.20180404165556-75cca531ea76.

5

What products are impacted by CVE-2021-3538?

CVE-2021-3538 impacts several products using the github.com/satori/go.uuid library, including IBM Edge Application Manager.

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