CVE-2025-8447Network attack vector

Private code disclosure via cross-repository comparisons

Published Aug 26, 2025 · Updated Aug 26, 2025

Improper access control in GitHub Enterprise Server 3.14 through 3.17 allows remote authenticated users to read limited private code. The compare/diff function accepts a cross-repository reference and returns code from a target repository without checking the requesting user's read authorization. Exploitation requires access to any repository plus the private repository name and a usable branch, tag, or commit SHA; disclosure is limited to code exposed by the generated diff.

CVSS severity7.0
High
EPSS probability0.31%
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 GitHub Enterprise Server 3.14 through 3.17 allows remote authenticated users to read limited private code. The compare/diff function accepts a cross-repository reference and returns code from a target repository without checking the requesting user's read authorization. Exploitation requires access to any repository plus the private repository name and a usable branch, tag, or commit SHA; disclosure is limited to code exposed by the generated diff.

The record

CVE
CVE-2025-8447
Published
Aug 26, 2025
Updated
Aug 26, 2025
Vendor
Twitter
Product
GitHub Enterprise Server
Classifications
CWE-639, T1213.003
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 26, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 26, 2025Record 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=3.14 <=3.14.16 changes=[{"at":"3.14.17","status":"unaffected"}]
  2. Affected versionversion=3.15 <=3.15.11 changes=[{"at":"3.15.12","status":"unaffected"}]
  3. Affected versionversion=3.16 <=3.16.7 changes=[{"at":"3.16.8","status":"unaffected"}]
  4. Affected versionversion=3.17 <=3.17.4 changes=[{"at":"3.17.5","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Twitter · GitHub Enterprise Serverversion=3.14 <=3.14.16 changes=[{"at":"3.14.17","status":"unaffected"}]; version=3.15 <=3.15.11 changes=[{"at":"3.15.12","status":"unaffected"}]; version=3.16 <=3.16.7 changes=[{"at":"3.16.8","status":"unaffected"}]; version=3.17 <=3.17.4 changes=[{"at":"3.17.5","status":"unaffected"}]

Published CVSS scores

4.8NISTCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
7.0GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key
T1213.003Code 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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