Missing cryptographic key commitment in the Amazon S3 Encryption Client for Go may allow a user with write access to the S3 bucket to introd
Noroxi assessment
Priority: Monitor (action score 24/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.10% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: github.com/aws/amazon-s3-encryption-client-go/v3 (Go) 4.0.0; github.com/aws/amazon-s3-encryption-client-go/v4 (Go) 4.0.0.
Low priority for now. Upgrade to github.com/aws/amazon-s3-encryption-client-go/v3 (Go) 4.0.0; github.com/aws/amazon-s3-encryption-client-go/v4 (Go) 4.0.0 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
Missing cryptographic key commitment in the Amazon S3 Encryption Client for Go may allow a user with write access to the S3 bucket to introduce a new EDK that decrypts to different plaintext when the encrypted data key is stored in an "instruction file" instead of S3's metadata record. To mitigate this issue, upgrade Amazon S3 Encryption Client for Go to version 4.0 or later.
- Published
- Dec 17, 2025
- Updated
- Sep 30, 2026
- EPSS
- 0.1% · 1th percentile
- CWE
- CWE-327
Report tools
Action score
24
Monitor
Low priority for now.
- CVSS
- 24 / 40 · 6.0 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · AMZN
- 5.3
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Check your site's encryption
This vulnerability is about certificate validation or weak cryptography. The free SSL checker tests your certificate, enabled TLS versions and weak ciphers.
Run the SSL checkVersions reported by the vendor
Affected version ranges reported by the assigning authority (AMZN). Independent of NVD's CPE analysis and usually ahead of it.
AWS S3 Encryption Client for Go
- 4.0not affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Go | github.com/aws/amazon-s3-encryption-client-go | from 0 | — |
| Go | github.com/aws/amazon-s3-encryption-client-go/v3 | from 0 | — |
| Go | github.com/aws/amazon-s3-encryption-client-go/v3 | before 4.0.0 | 4.0.0 |
| Go | github.com/aws/amazon-s3-encryption-client-go/v4 | before 4.0.0 | 4.0.0 |
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Go:github.com/aws/amazon-s3-encryption-client-go/v3 | 4.0.0 | Package registry (OSV) |
| Go:github.com/aws/amazon-s3-encryption-client-go/v4 | 4.0.0 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- X
Weakness class (CWE)
CWE-327 · Use of a Broken or Risky Cryptographic AlgorithmCVSS vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Encryption Brute ForcingCAPEC-20likelihood: Low · Low
- Creating a Rogue Certification Authority CertificateCAPEC-459likelihood: Medium · Very High
- Signature SpoofCAPEC-473
- Signature Spoofing by Improper ValidationCAPEC-475likelihood: Low · High
- Cryptanalysis of Cellular EncryptionCAPEC-608High
- Rooting SIM CardsCAPEC-614High
- CryptanalysisCAPEC-97likelihood: Low · Very High
Change log
- Fix✗ → ✓
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References
Show all references (2 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.