CVE-2015-0843Network attack vector

Memory corruption via unbounded sprintf writes

Published Jun 26, 2025 · Updated Jun 27, 2025

Buffer overflows in YubiServer before 0.6 allow remote attackers to corrupt process memory through crafted validation requests. Fixed-size query and log buffers in the server and administration code receive request or database strings through unbounded sprintf calls. No authentication or user interaction is required; published sources do not establish whether exploitation stops at a server crash or enables code execution.

CVSS severity9.8
Critical
EPSS probability0.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflows in YubiServer before 0.6 allow remote attackers to corrupt process memory through crafted validation requests. Fixed-size query and log buffers in the server and administration code receive request or database strings through unbounded sprintf calls. No authentication or user interaction is required; published sources do not establish whether exploitation stops at a server crash or enables code execution.

The record

CVE
CVE-2015-0843
Published
Jun 26, 2025
Updated
Jun 27, 2025
Vendor
Chrysostomos Nanakos
Product
YubiServer
Classifications
CWE-120, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 26, 2025CVE publishedPublication date reported by the CVE source.
  2. Jun 27, 2025Record 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 <0.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Chrysostomos Nanakos · YubiServerversion=0 <0.6

Published CVSS scores

9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 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-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1190Exploit Public-Facing Application

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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