CVE-2026-32144Network attack vector

OCSP authorization bypass via missing signature verification

Published Apr 7, 2026 · Updated Apr 7, 2026

Improper certificate validation in affected Erlang/OTP releases allows man-in-the-middle attackers to make clients accept revoked certificates. The pubkey_ocsp:is_authorized_responder/3 routine trusts a designated responder when issuer names and OCSPSigning usage match, without verifying its certificate signature against the issuing CA. Exploitation requires OCSP stapling, which is disabled by default, or direct use of pkix_ocsp_validate/5; a forged response bypasses revocation checks and can expose data sent to a compromised server.

CVSS severity7.6
High
EPSS probability0.20%
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 affected Erlang/OTP releases allows man-in-the-middle attackers to make clients accept revoked certificates. The pubkey_ocsp:is_authorized_responder/3 routine trusts a designated responder when issuer names and OCSPSigning usage match, without verifying its certificate signature against the issuing CA. Exploitation requires OCSP stapling, which is disabled by default, or direct use of pkix_ocsp_validate/5; a forged response bypasses revocation checks and can expose data sent to a compromised server.

The record

CVE
CVE-2026-32144
Published
Apr 7, 2026
Updated
Apr 7, 2026
Vendor
Erlang
Product
Erlang/OTP
Classifications
CWE-295, CAPEC-459, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 7, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 7, 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=11.2 <* changes=[{"at":"11.5.4","status":"unaffected"},{"at":"11.2.12.7","status":"unaffected"}]
  2. Affected versionversion=1.16 <* changes=[{"at":"1.20.3","status":"unaffected"},{"at":"1.17.1.2","status":"unaffected"}]
  3. Affected versionversion=27.0 <* changes=[{"at":"28.4.2","status":"unaffected"},{"at":"27.3.4.10","status":"unaffected"}]
  4. Affected versionversion=601a012837ea0a5c8095bf24223132824177124d <* changes=[{"at":"ac7ff528be857c5d35eb29c7f24106e3a16d4891","status":"unaffected"},{"at":"49033a6d93a5be0ee0dce04e1fb8b4ae7de1e0c0","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Erlang · Erlang/OTPversion=11.2 <* changes=[{"at":"11.5.4","status":"unaffected"},{"at":"11.2.12.7","status":"unaffected"}]; version=1.16 <* changes=[{"at":"1.20.3","status":"unaffected"},{"at":"1.17.1.2","status":"unaffected"}]; version=27.0 <* changes=[{"at":"28.4.2","status":"unaffected"},{"at":"27.3.4.10","status":"unaffected"}]; version=601a012837ea0a5c8095bf24223132824177124d <* changes=[{"at":"ac7ff528be857c5d35eb29c7f24106e3a16d4891","status":"unaffected"},{"at":"49033a6d93a5be0ee0dce04e1fb8b4ae7de1e0c0","status":"unaffected"}]

Published CVSS scores

7.6Erlang Ecosystem FoundationCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:L/SI:L/SA:N
7.4NISTCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 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
CAPEC-459Creating a Rogue Certification Authority Certificate
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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