What is CVE-2026-9312?
A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to send crafted requests to internal services by exploiting insufficient input validation in an upload endpoint. By injecting path traversal content into request parameters, an attacker could bypass the intended request flow and redirect internal API calls, potentially accessing internal services and exposing sensitive credentials. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.16.20, 3.17.17, 3.18.11, 3.19.8, 3.20.4, and 3.21.1. This vulnerability was reported via the GitHub Bug Bounty program.
The record classifies CVE-2026-9312 under weakness class CWE-918. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 131 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 8.2 — HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N - CVSS v4.0 base score
- 9.2
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - EPSS (FIRST)
- 0.0% probability of exploitation in the next 30 days, higher than 15.7% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 4.7/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-05-27, last modified 2026-05-28
Is CVE-2026-9312 being exploited?
It currently carries a trending score of 9 in the Threadlinqs vulnerability feed.
Affected products and versions
- GitHub: Enterprise Server
How to fix CVE-2026-9312
No vendor patch reference has been recorded for CVE-2026-9312 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-9312
1 tracked threat in the Threadlinqs corpus references CVE-2026-9312, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Seeded from cveorg and not yet processed by the Threadlinqs enrichment pipeline, so blank CVSS, EPSS or KEV fields above mean NOT MEASURED rather than measured-absent.