Security readout for executives and security teams
Plain-English summary
Mbed TLS could leave previously read plaintext application data in memory after mbedtls_ssl_read. That creates a confidentiality concern if another bug, dump, or privileged access exposes process memory. The sources do not show active exploitation or a CVSS score.
Executive priority
Treat this as a targeted remediation item for systems handling sensitive data. It lacks confirmed exploitation evidence, but plaintext memory retention can increase impact if memory disclosure, crash dumps, or privileged compromise occurs.
Technical view
CVE-2020-36476 affects Mbed TLS before 2.24.0, before 2.16.8 LTS, and before 2.7.17 LTS. The issue is missing zeroization of unused plaintext buffers in mbedtls_ssl_read, meaning sensitive application data may remain in memory longer than intended.
Likely exposure
Exposure is limited to software, firmware, or services that include affected Mbed TLS versions. Inventory may need component-level review because the CVE source lists no specific downstream products or package names beyond Mbed TLS.
Exploitation context
The bundle marks KEV as false and provides no cited evidence of active exploitation. The described weakness is memory-residue exposure, not a standalone remote code execution path in the provided sources.
Researcher notes
Primary evidence is limited to the CVE description and release/advisory references. No CVSS vector, CWE, exploit report, or product-specific exposure list is provided, so validation should focus on version presence and vendor patch confirmation.
Mitigation direction
- Upgrade Mbed TLS to 2.24.0, 2.16.8 LTS, 2.7.17 LTS, or later.
- Apply vendor or distribution security updates for packaged Mbed TLS builds.
- Check Debian LTS advisories if using Debian-maintained packages.
- Ask product vendors whether embedded Mbed TLS versions include the zeroization fix.
Validation and detection
- Identify all direct and transitive uses of Mbed TLS.
- Confirm runtime or build versions are not below the fixed release lines.
- Review firmware and appliance SBOMs for bundled Mbed TLS.
- Verify package changelogs reference CVE-2020-36476 or the relevant fixed release.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2020-36476 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.17CVE reference
- https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.8CVE reference
- https://github.com/ARMmbed/mbedtls/releases/tag/v2.24.0CVE reference
- [debian-lts-announce] 20211123 [SECURITY] [DLA 2826-1] mbedtls security updateCVE reference · mailing-list
- [debian-lts-announce] 20221225 [SECURITY] [DLA 3249-1] mbedtls security updateCVE reference · mailing-list
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.