CVE-2023-23763Network attack vector

Private repository disclosure via retained fork access

Published Sep 1, 2023 · Updated Oct 1, 2024

Incorrect authorization in GitHub Enterprise Server before 3.10.0 allows remote attackers to read an upstream private repository through a fork. GitHub has not published the specific code path; the disclosed authorization failure leaves the fork's prior upstream read access intact after the visibility transition. A preexisting fork relationship and a repository visibility change are required, and exposure is limited to read access to upstream private content.

CVSS severity5.3
Medium
EPSS probability0.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Incorrect authorization in GitHub Enterprise Server before 3.10.0 allows remote attackers to read an upstream private repository through a fork. GitHub has not published the specific code path; the disclosed authorization failure leaves the fork's prior upstream read access intact after the visibility transition. A preexisting fork relationship and a repository visibility change are required, and exposure is limited to read access to upstream private content.

The record

CVE
CVE-2023-23763
Published
Sep 1, 2023
Updated
Oct 1, 2024
Vendor
Twitter
Product
GitHub Enterprise Server
Classifications
CWE-862, CWE-200, T1213.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 1, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 1, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.6.0 <3.6.18
  2. Affected versionversion=3.7.0 <3.7.16
  3. Affected versionversion=3.8.0 <3.8.9
  4. Affected versionversion=3.9.0 <3.9.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Twitter · GitHub Enterprise Serverversion=3.6.0 <3.6.18; version=3.7.0 <3.7.16; version=3.8.0 <3.8.9; version=3.9.0 <3.9.4

Published CVSS scores

5.3GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.3NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/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-862Missing Authorization
CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1213.003Data from Information Repositories: Code 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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo