CVE-2026-82331Public exploitHinoki check available

Host file writes via tar symlink escape

Published Sep 23, 2026 · Updated Sep 23, 2026

Link following in Apache BuildStream 2.8.0 and earlier on Python before 3.12 allows attackers to write host files via crafted tarballs. The tar source plugin prechecks archive members before extraction but then follows symlinks whose targets escape the staging directory. Exploitation requires a project to fetch an untrusted or replaced source archive, and writes carry the BuildStream user's privileges.

CVSS severityUnavailable
Unscored
EPSS probability0.42%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Link following in Apache BuildStream 2.8.0 and earlier on Python before 3.12 allows attackers to write host files via crafted tarballs. The tar source plugin prechecks archive members before extraction but then follows symlinks whose targets escape the staging directory. Exploitation requires a project to fetch an untrusted or replaced source archive, and writes carry the BuildStream user's privileges.

The record

CVE
CVE-2026-82331
Published
Sep 23, 2026
Updated
Sep 23, 2026
Vendor
Apache Software Foundation
Product
Apache BuildStream
Classifications
CWE-59, CAPEC-132
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 23, 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 <=2.8.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

Apache Software Foundation · Apache BuildStreamversion=0 <=2.8.0

Published CVSS scores

No CVSS assessment is available in this record.

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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-59Improper Link Resolution Before File Access ('Link Following')
CAPEC-132Symlink Attack

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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