CVE-2026-77987

Published: Set 22, 2026 Last Modified: Set 24, 2026
ExploitDB:
Other exploit source:
Google Dorks:
CRITICAL 9,3
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Confidentiality: N/A
Integrity: N/A
Availability: N/A

Description

AI Translation Available

A server-side request forgery (SSRF) vulnerability was identified in the notebook viewer of GitHub Enterprise Server. The notebook viewer validated the scheme and host of a user-supplied URL but did not validate the port, allowing requests to be directed to internal services listening on other ports of the same appliance. Response bodies were not returned to the requester, but response timing acted as an oracle that allowed instance secrets to be extracted character by character. An extracted secret could then be used in a separate interaction with an internal service to obtain remote code execution on the appliance. Exploitation required network access to the instance and was unauthenticated when private mode was disabled, or required any authenticated user when private mode was enabled. This vulnerability affected GitHub Enterprise Server versions 3.17 through 3.22 and was fixed in versions 3.22.1, 3.21.6, 3.20.8, 3.19.12, 3.18.15, and 3.17.21. This vulnerability was reported through the GitHub Bug Bounty program.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0089
Percentile
0,6th
Updated

Single Data Point

Only one EPSS measurement is available for this CVE. Trend analysis requires multiple data points over time.

208

Observable Timing Discrepancy

Incomplete
Common Consequences
Security Scopes Affected:
Confidentiality Access Control
Potential Impacts:
Read Application Data Bypass Protection Mechanism
Applicable Platforms
All platforms may be affected
View CWE Details
918

Server-Side Request Forgery (SSRF)

Incomplete
Common Consequences
Security Scopes Affected:
Confidentiality Integrity Access Control
Potential Impacts:
Read Application Data Execute Unauthorized Code Or Commands Bypass Protection Mechanism
Applicable Platforms
Technologies: Web Based, AI/ML, Web Server
View CWE Details
https://docs.github.com/en/[email protected]/admin/release-notes#3.17.21
https://docs.github.com/en/[email protected]/admin/release-notes#3.18.15
https://docs.github.com/en/[email protected]/admin/release-notes#3.19.12
https://docs.github.com/en/[email protected]/admin/release-notes#3.20.8
https://docs.github.com/en/[email protected]/admin/release-notes#3.21.6
https://docs.github.com/en/[email protected]/admin/release-notes#3.22.1