CVE-2026-87736Network attack vector

Service interruption via undersized compressed EC keys

Published Sep 9, 2026 · Updated Sep 9, 2026

Out-of-bounds read in OCaml mirage-crypto-ec before 2.3.0 allows remote authenticated users to interrupt services with compressed EC keys. Point.of_octets processes undersized compressed-point buffers without a length check and raises an exception in P-256, P-384, and P-521 operations. The affected paths are Dsa.pub_of_octets and Dh.key_exchange; an uncaught exception can terminate the calling operation or service.

CVSS severity4.3
Medium
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in OCaml mirage-crypto-ec before 2.3.0 allows remote authenticated users to interrupt services with compressed EC keys. Point.of_octets processes undersized compressed-point buffers without a length check and raises an exception in P-256, P-384, and P-521 operations. The affected paths are Dsa.pub_of_octets and Dh.key_exchange; an uncaught exception can terminate the calling operation or service.

The record

CVE
CVE-2026-87736
Published
Sep 9, 2026
Updated
Sep 9, 2026
Vendor
OCaml
Product
mirage-crypto-ec
Classifications
CWE-125, CWE-248
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 9, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 9, 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 <2.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

OCaml · mirage-crypto-ecversion=0 <2.3.0

Published CVSS scores

4.3OCaml Security AdvisoriesCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read
CWE-248Uncaught Exception

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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