dbcve.org
UuidApplication · Satori

CVE-2021-3538

CRITICAL · 9.8 CVSS v3.1 Published 2021-06-02
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The satori/go.uuid library uses insecure randomness in its g.rand.Read function, making generated UUIDs predictable rather than random. This affects UUIDs generated during the vulnerable commit range, allowing attackers to potentially enumerate or predict UUID values used for identifiers, sessions, or tokens.

MitigationUpdate to a newer version of go.uuid that uses cryptographically secure random number generation (crypto/rand), or migrate to an alternative UUID library that properly implements secure randomness.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
UuidApplication
Affected:all versions

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify satori/go.uuid in dependencies
    Run 'grep -r "satori/go.uuid" go.mod' or 'go list -m all | grep uuid' to find if the library is included in your project
    Affected if The satori/go.uuid library appears in your go.mod or module list
  2. Check import statements
    Search your codebase with 'grep -r "github.com/satori/go.uuid"' to find where this library is imported
    Affected if Code imports github.com/satori/go.uuid
  3. Verify UUID generation usage
    Search for 'uuid.New()' or 'uuid.NewV4()' calls in your code to see where UUIDs are being generated
    Affected if Your code calls UUID generation functions from this library
  4. Inspect library source for insecure randomness
    Examine the vendor directory or module cache: locate the uuid.go file under satori/go.uuid and look for 'rand.Read' without crypto/rand usage
    Affected if The library source uses math/rand or crypto/rand.Read for UUID generation (vulnerable if using insecure randomness)
  5. Check for cryptographic secure alternatives
    Review go.mod for alternative UUID libraries like github.com/google/uuid or github.com/gofrs/uuid
    Affected if You are using satori/go.uuid and no secure alternative is present

You are affected if your codebase imports and uses the satori/go.uuid library for UUID generation, as all versions of this library use insecure randomness.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update to a newer version of go.uuid that uses cryptographically secure random number generation (crypto/rand), or migrate to an alternative UUID library that properly implements secure randomness.

Recommended fix High confidence

Replace with github.com/google/uuid (the actively maintained fork that uses crypto/rand)

  1. 1. Identify the current version of github.com/satori/go.uuid in use by checking go.mod
  2. 2. Stop using github.com/satori/go.uuid as it is no longer maintained
  3. 3. Replace with github.com/google/uuid (the recommended maintained fork)
  4. 4. Run: go get github.com/google/uuid@latest
  5. 5. Update import statements from 'github.com/satori/go.uuid' to 'github.com/google/uuid'
  6. 6. Update any code using uuid.NewV4() to uuid.New()
  7. 7. Run go mod tidy to clean up dependencies
  8. 8. Rebuild and test the application
Caveat The import path changes from github.com/satori/go.uuid to github.com/google/uuid; function calls remain similar but verify API compatibility

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Uuid Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-3538 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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