Heap double-free in AWS Common Runtime aws-c-http
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-415 and the CVSS impact.
Summary
Improper handling of HPACK dynamic table size updates in the AWS Common Runtime aws-c-http library might allow a remote threat actor operating a server to cause memory corruption on a connecting client application, potentially leading to arbitrary code execution, via a crafted sequence of HTTP/2 HEADERS frames. To remediate this issue, users should upgrade to aws-c-http version 0.11.0.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2026-12043
References
More AWS vulnerabilities
- TI-2026-23989 crypto: algif_aead - Revert to operating out-of-place KEVCVSS 3.1HIGH 7.8
- TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
- TI-2024-18648 Amazon AWS Amplify CLI before 12.10.1 incorrectly configures the role trust policy of IAM… CVSS 3.1CRITICAL 9.8
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- TI-2025-03847 Input validation issue in AWS Amplify Studio UI component properties CVSS 4.0CRITICAL 9.0
- TI-2026-11603 HTTP/2 Stream Parser Confusion Body-Inspection Bypass in Amazon CloudFront with AWS WAF CVSS 4.0HIGH 7.9
Sources
- CVE-2026-12043 · CVE Program
- CVE-2026-12043 · NVD
- FIRST EPSS
- CVE-2026-12043 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences