CVE-2026-48090

Envoy HTTP: OAuth2 filter late async token completion after stream teardown (UAF / crash risk)

MEDIUM
5.9
CVSS Score
Published: June 26, 2026 at 06:03 PM UTC
Updated: October 25, 2026 at 05:10 PM UTC
1 product affected across 1 vendorEnvoy

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Severity
MEDIUM5.9
Exploit prediction
EPSS 0.6%
SSVC
PoC

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.37.0 until 1.37.5 and 1.38.3, the HTTP OAuth2 filter (envoy.filters.http.oauth2) can leave an in-flight async token exchange attached to a downstream stream that has already been torn down. A late AsyncClient completion can still invoke OAuth2Filter methods that use StreamDecoderFilterCallbacks after that object’s lifetime has ended, causing undefined behavior, worker crashes (availability loss), and use-after-free / invalid-vptr failures under AddressSanitizer. This is a memory-safety / lifetime issue in the data plane, not a trivial config bug. Remote code execution is not claimed here; the primary demonstrated impact is DoS via crash and UB; any further impact would be deployment- and allocator-dependent. This vulnerability is fixed in 1.37.5 and 1.38.3.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

1.37.0 ≤ v < 1.37.51.38.0 ≤ v < 1.38.3
Affected range stops below 1.37.5, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.38.3, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

x_refsource_CONFIRMExploitMitigationVendor Advisory
Source: cverecord
https://github.com/envoyproxy/envoy/security/advisories/GHSA-3cj2-c63f-q26f

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.9MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-416

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