CVE-2020-8021Network attack vector

Unauthenticated package-file disclosure via service-created _link

Published May 19, 2020 · Updated Sep 16, 2024

Improper access control in Open Build Service before 2.10.5 allows remote attackers to read source-disabled package files. The mergeservicerun routine in src/backend/bs_srcserver accepts a service-produced filename targeting _link and copies that output as a package link. A crafted _service file therefore bypasses source-access restrictions and exposes package contents without authentication.

CVSS severity5.3
Medium
EPSS probability1.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Open Build Service before 2.10.5 allows remote attackers to read source-disabled package files. The mergeservicerun routine in src/backend/bs_srcserver accepts a service-produced filename targeting _link and copies that output as a package link. A crafted _service file therefore bypasses source-access restrictions and exposes package contents without authentication.

The record

CVE
CVE-2020-8021
Published
May 19, 2020
Updated
Sep 16, 2024
Vendor
OpenSUSE
Product
Open Build Service
Classifications
CWE-269, T1213
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 19, 2020CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record 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=Open Build Service <2.10.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OpenSUSE · Open Build Serviceversion=Open Build Service <2.10.5

Published CVSS scores

5.3SUSECVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
4.3NIST NVDAV:N/AC:M/Au:N/C:P/I:N/A:N

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.

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

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-269Improper Privilege Management
T1213Data from Information Repositories

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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