CVE-2026-59251Network attack vector

Denial of service via exponential policy tree growth

Published Jul 27, 2026 · Updated Jul 27, 2026

Resource exhaustion in Erlang/OTP public_key allows remote attackers to interrupt the BEAM VM via crafted TLS certificate chains. During RFC 5280 path validation, pubkey_policy_tree:add_leaves/2 and add_leaf_siblings/2 expand every policy across every certificate without bounding the resulting M^K tree. Any TLS client or mutual-TLS server that validates a peer certificate chain is exposed; scheduler saturation and memory exhaustion terminate the entire VM.

CVSS severity8.7
High
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in Erlang/OTP public_key allows remote attackers to interrupt the BEAM VM via crafted TLS certificate chains. During RFC 5280 path validation, pubkey_policy_tree:add_leaves/2 and add_leaf_siblings/2 expand every policy across every certificate without bounding the resulting M^K tree. Any TLS client or mutual-TLS server that validates a peer certificate chain is exposed; scheduler saturation and memory exhaustion terminate the entire VM.

The record

CVE
CVE-2026-59251
Published
Jul 27, 2026
Updated
Jul 27, 2026
Vendor
Erlang
Product
Erlang/OTP
Classifications
CWE-770, CAPEC-130, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 27, 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=1.15 <* changes=[{"at":"1.21.4","status":"unaffected"},{"at":"1.20.3.4","status":"unaffected"},{"at":"1.17.1.5","status":"unaffected"}]
  2. Affected versionversion=26.2 <* changes=[{"at":"29.0.4","status":"unaffected"},{"at":"28.5.0.4","status":"unaffected"},{"at":"27.3.4.15","status":"unaffected"}]
  3. Affected versionversion=9d1dda7bad5a64b58c10a1554751689e94131a73 <* changes=[{"at":"f8580fc117098c08165f46c26fd0750c5cfb2a90","status":"unaffected"},{"at":"f04c6bba38de1cf1b1836a7d9a9fbe239bd939e8","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Erlang · Erlang/OTPversion=1.15 <* changes=[{"at":"1.21.4","status":"unaffected"},{"at":"1.20.3.4","status":"unaffected"},{"at":"1.17.1.5","status":"unaffected"}]; version=26.2 <* changes=[{"at":"29.0.4","status":"unaffected"},{"at":"28.5.0.4","status":"unaffected"},{"at":"27.3.4.15","status":"unaffected"}]; version=9d1dda7bad5a64b58c10a1554751689e94131a73 <* changes=[{"at":"f8580fc117098c08165f46c26fd0750c5cfb2a90","status":"unaffected"},{"at":"f04c6bba38de1cf1b1836a7d9a9fbe239bd939e8","status":"unaffected"}]

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.7Erlang Ecosystem FoundationCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L

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.

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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-770Allocation of Resources Without Limits or Throttling
CAPEC-130Excessive Allocation
T1499Endpoint Denial of Service

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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