CVE-2026-46344Public exploitNetwork attack vector

Process crash via OID-controlled signature-buffer overread

Published May 29, 2026 · Updated May 29, 2026

Out-of-bounds read in XMSS verification in Open Quantum Safe liboqs before 0.16.0 allows remote attackers to crash verifying processes. The XMSS and XMSS^MT wrappers accept a signature length for the declared variant, but xmss_sign_open and xmssmt_sign_open reparse an untrusted public-key OID and use its larger sig_bytes value to index that signature buffer. Reachability requires an application to verify a signature with an untrusted or tampered public key; the overread feeds only an internal hash and can crash the process if it reaches an unmapped page, without disclosing data or accepting an invalid signature.

CVSS severity5.3
Medium
EPSS probability0.30%
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 XMSS verification in Open Quantum Safe liboqs before 0.16.0 allows remote attackers to crash verifying processes. The XMSS and XMSS^MT wrappers accept a signature length for the declared variant, but xmss_sign_open and xmssmt_sign_open reparse an untrusted public-key OID and use its larger sig_bytes value to index that signature buffer. Reachability requires an application to verify a signature with an untrusted or tampered public key; the overread feeds only an internal hash and can crash the process if it reaches an unmapped page, without disclosing data or accepting an invalid signature.

The record

CVE
CVE-2026-46344
Published
May 29, 2026
Updated
May 29, 2026
Vendor
Open Quantum Safe
Product
liboqs
Classifications
CWE-125, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 29, 2026CVE publishedPublication date reported by the CVE source.
  2. May 29, 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=< 0.16.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Open Quantum Safe · liboqsversion=< 0.16.0

Published CVSS scores

5.3GitHub Security AdvisoryCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A: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 exploitPublished

Weakness, pattern, technique

CWE-125Out-of-bounds Read
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

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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