Use-after-free in the SetClient command handler of kmstool-enclave in AWS aws-nitro-enclaves-sdk-c
Only enclave images that include kmstool-enclave, or code derived from it, are affected, in aws-nitro-enclaves-sdk-c v0.4.5 and earlier. The fix is in v0.4.6.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Fix
- Fixed in 0.4.6
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
The kmstool-enclave sample application in AWS's aws-nitro-enclaves-sdk-c library is affected, along with any enclave images built from it or derived code. A flaw in its SetClient command handler could let a process on the parent EC2 instance corrupt memory inside a Nitro Enclave, potentially enabling arbitrary code execution within the enclave.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original description
A use-after-free and double-free issue in the SetClient command handler of the kmstool-enclave sample application of AWS aws-nitro-enclaves-sdk-c before 0.4.6 may allow an application that runs on the parent EC2 instance to corrupt heap memory inside a Nitro Enclave which may lead to arbitrary code execution within the enclave. To remediate this issue, users should rebuild any enclave image that includes kmstool-enclave, or code derived from it, against aws-nitro-enclaves-sdk-c 0.4.6.
Timeline
- CVE published
- First seen by cve.now
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- AWS kmstool-enclave
fixed in 0.4.6
References 3
GitHub · aws/aws-nitro-enclaves-sdk-c
aws.amazon.com
Questions about CVE-2026-119116
What does this mean?
The SetClient command handler in kmstool-enclave frees memory and then uses it again (a use-after-free). This corrupts heap memory inside the enclave, which may lead to arbitrary code execution within the enclave.Source: github.com
Am I affected, and how do I check?
The issue affects enclave images that include kmstool-enclave, or code derived from it, built with aws-nitro-enclaves-sdk-c v0.4.5 or earlier. To check, look at whether the enclave image includes kmstool-enclave and which version of aws-nitro-enclaves-sdk-c it was built from.Source: github.com
What should I do about it?
Upgrade to aws-nitro-enclaves-sdk-c v0.4.6, which addresses the issue. The advisory states there are no workarounds, so upgrading is required.Source: github.com
Is it being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data