CVE-2021-3538
go.uuid has Predictable UUID Identifiers
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2021-3538- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-338
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2021-3538- Weakness
- CWE-338
- Updated
- 2026-11-02
EUVDEUVD-2023-0607 No score
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.
- Record
EUVD-2023-0607- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-33m6-q9v5-62r7
go.uuid has Predictable UUID Identifiers
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/[email protected]
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
- Record
GHSA-33m6-q9v5-62r7- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-338
- Updated
- 2026-11-02
OSVGHSA-33m6-q9v5-62r7
go.uuid has Predictable UUID Identifiers
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/[email protected]
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
- Record
GHSA-33m6-q9v5-62r7- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-338
- Updated
- 2026-11-02
OSVGO-2022-0244 No score
Insufficient randomness in UUIDs in github.com/satori/go.uuid
Random data used to create UUIDs can contain zeros, resulting in predictable UUIDs and possible collisions.
- Record
GO-2022-0244- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/satori/go.uuidGo |
1.2.1-0.20180103161547-0ef6afb2f6cd up to 1.2.1-0.20180404165556-75cca531ea76 | 1.2.1-0.20180404165556-75cca531ea76 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-3538 is a critical vulnerability (CVSS 9.8) in Satori Uuid, published June 2, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.31%, the 83rd percentile. Fixed in github.com/satori/go.uuid 1.2.1-0.20180404165556-75cca531ea76.