Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A10:2025 - Mishandling of Exceptional Conditions
ASVS 5.0
V16 - Security Logging and Error Handling Null pointer safety, defensive checks
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | Typically causes application crash (denial of service). In some cases, may be exploitable for code execution on systems without memory protection. With a CVSS score of 6.5 (MEDIUM), this represents a moderate risk. |
| Exploit ScenarioDerived | An attacker provides input that causes a code path where a pointer is dereferenced without a prior NULL check, crashing the application. |
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Alert meAnalysisAIv1 – Mar 15, 2026
Envoy is a high-performance edge/middle/service proxy. In 1.33.12, 1.34.10, 1.35.6, 1.36.2, and earlier, Envoy crashes when JWT authentication is configured with the remote JWKS fetching, allow_missing_or_failed is enabled, multiple JWT tokens are present in the request headers and the JWKS fetch fails. This is caused by a re-entry bug in the JwksFetcherImpl. When the first token's JWKS fetch fails, onJwksError() callback triggers processing of the second token, which calls fetch() again on the same fetcher object. The original callback's reset() then clears the second fetch's state (receiver_ and request_) which causes a crash when the async HTTP response arrives.
Earlier versions of this analysis (1)
RemediationAI
Add NULL checks before pointer dereference operations. Use static analysis to identify potential NULL pointer issues. Enable compiler warnings.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 2 packages in go, euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
A NULL pointer dereference occurs when the application attempts to use a pointer that has not been initialized or has been set to NULL.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Primary rating from Vendor (github).
CVSS VectorVendor: github
Lifecycle Timeline
3Executive ViewAI
Organizations using Envoy should be aware of notable risk from CVE-2025-64527, a null pointer dereference vulnerability rated CVSS 6.5. Exploitation could compromise the security of affected deployments. Proof-of-concept code is publicly available. Organizations should apply vendor updates when available and monitor for exploitation.
Apply vendor patch. If patching is delayed: enable ASLR/DEP, apply network segmentation.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A null pointer dereference occurs when a program attempts to access memory through a pointer that has been set to NULL (address 0x0).
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
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Same weakness CWE-476 – NULL Pointer Dereference
View allSame technique Denial Of Service
View allVendor StatusVendor
Debian
Bug #987544| Release | Status | Fixed Version | Urgency |
|---|---|---|---|
| open | - | - |
EUVD-2025-201100
GHSA-mp85-7mrq-r866
NVD
CVE.org
EPSS
VulDB
Exploit-DB