CVE-2026-40944Network attack vector

mTLS connection rejection via single-block CA parsing

Published Apr 21, 2026 · Updated Apr 21, 2026

Improper certificate validation in Oxia before 0.16.2 allows remote attackers to trigger rejection of mTLS connections requiring a CA chain. The trustedCertPool() function in common/security/tls.go calls pem.Decode() once and silently discards every remaining certificate block. Exposure requires a trustedCaFile containing multiple certificates; properly chained clients are then rejected as having an unknown certificate authority.

CVSS severity6.9
Medium
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper certificate validation in Oxia before 0.16.2 allows remote attackers to trigger rejection of mTLS connections requiring a CA chain. The trustedCertPool() function in common/security/tls.go calls pem.Decode() once and silently discards every remaining certificate block. Exposure requires a trustedCaFile containing multiple certificates; properly chained clients are then rejected as having an unknown certificate authority.

The record

CVE
CVE-2026-40944
Published
Apr 21, 2026
Updated
Apr 21, 2026
Vendor
Oxia
Product
Oxia
Classifications
CWE-295
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.16.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Oxia · Oxiaversion=< 0.16.2

Published CVSS scores

6.9GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-295Improper Certificate Validation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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