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CVE-2026-5845: Github Enterprise Server Insecure Direct Object Reference (CVSS 7.2)

CVE-2026-5845 is a high severity insecure direct object reference in Github Enterprise Server with a CVSS score of 7.2. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.

Last updated: Jun 17, 2026

Quick answer

Direct answer

CVE-2026-5845 is a high severity insecure direct object reference in Github Enterprise Server with a CVSS score of 7.2. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.

Risk scores

CVSS base score
7.2HIGH
EPSS probability
0.48%
Higher than 40 percent of all CVEs
CISA KEV
Not listed
CVSS metricWhat it means
Attack vector (AV:L)Local access needed
Attack complexity (AC:L)Low complexity
Attack requirements (AT:P)Attack requirements present
Privileges required (PR:L)Low privileges required
User interaction (UI:N)No user interaction
Confidentiality (VC:H)High confidentiality impact
Integrity (VI:H)High integrity impact
Availability (VA:N)No availability impact

CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:L/SI:L/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

About Github Enterprise Server

CVE-2026-5845 affects Github Enterprise Server, a product from Github. Before acting, confirm where Github Enterprise Server runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.

What the flaw is

In plain terms: An improper authorization vulnerability in scoped user-to-server (ghu_) token authorization in GitHub Enterprise Server allows an authenticated attacker to access private repositories outside the intended installation scope, which can include write operations, via an authorization fallback that treated a revoked/deleted installation as a global installation context, which could be chained with token revocation timing and SSH push attribution to obtain and reuse a victim-scoped token. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.20.1, 3.19.5, 3.18.8, 3.17.14, 3.16.17, 3.15.21, and 3.14.26. This vulnerability was reported via the GitHub Bug Bounty program.

The weakness class is Insecure Direct Object Reference. Changing an ID in a request exposes another user's data.

Based on its CVSS vector, the flaw needs local or adjacent access, needs some level of access, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.

Affected versions and timeline

FieldDetail
ProductGithub Enterprise Server
Affected versionsEnterprise Server before 3.14.26; Enterprise Server from 3.15.0 before 3.15.21; Enterprise Server from 3.16.0 before 3.16.17; Enterprise Server from 3.17.0 before 3.17.14; Enterprise Server from 3.18.0 before 3.18.8; Enterprise Server from 3.19.0 before 3.19.5; Enterprise Server 3.20.0
PublishedApr 21, 2026
Last modifiedJun 17, 2026
Added to CISA KEVNot listed
Assigning CNAproduct-cna@github.com

How to detect it

  • Inventory every instance of Github Enterprise Server and record the running version against the affected range above.
  • Check external attack surface scans for internet facing instances of the component.
  • Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
  • Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.

How to fix it

  • Apply the fixed version of Github Enterprise Server named in the vendor advisory.
  • If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
  • Rescan after the change to prove the exposure is gone, then close the ticket.

CTEM action plan

CTEM stageWhat to do for this CVE
ScopeAdd every business service that depends on Github Enterprise Server to the current CTEM cycle.
DiscoverFind all instances, including shadow and cloud deployments, and record versions and exposure.
PrioritizeRank using EPSS and CVSS together with asset exposure and business impact.
ValidateConfirm the flaw is reachable and exploitable in your environment and that compensating controls work.
MobilizeAssign the fix to the asset owner with a due date matched to the priority, then verify closure.

CWE References

Technical References

Frequently asked questions

CVE-2026-5845 is a high severity insecure direct object reference in Github Enterprise Server with a CVSS score of 7.2. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.

Related CVEs

HIGH8.7
CVE-2026-96890
Github Enterprise Server

A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed a repository contributor to cause the appliance to issue requests to attacker-controlled internal hosts, which could be chained to achieve remote code execution on the appliance. The secret scanning validator for GCP service account credentials trusted the token endpoint embedded in a committed credential and issued a request to it without restricting the destination. Exploitation required an authenticated user with permission to push to a repository on an instance with GitHub Advanced Security and secret scanning validity checks enabled, a non-default configuration. This vulnerability affected GitHub Enterprise Server 3.20, 3.21, and 3.22 and was fixed in versions 3.20.9, 3.21.7, and 3.22.2. This vulnerability was reported through the GitHub Bug Bounty program.

Oct 6, 2026
CRITICAL9.3
CVE-2026-77987
Github Enterprise Server

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.

Sep 22, 2026
HIGH7.7
CVE-2026-76851
Github Enterprise Server

A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed remote code execution on the instance. Insufficient network isolation allowed malicious pre-receive hook code to impersonate an internal service and redirect trusted internal requests to a privileged service, leading to elevated code execution. Exploitation required pre-receive hook networking to be enabled and either site administrator privileges or write access to a repository containing a configured pre-receive hook. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.20, 3.18.14, 3.19.11, 3.20.7, and 3.21.5. This vulnerability was reported via the GitHub Bug Bounty program.

Sep 1, 2026
HIGH7.7
CVE-2026-19118
Github Enterprise Server

A time-of-check time-of-use race condition vulnerability was identified in GitHub Enterprise Server that allowed remote code execution. Exploitation required an authenticated user with write access to a repository and precise timing of concurrent upload requests. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.20, 3.18.14, 3.19.11, 3.20.7, and 3.21.5. This vulnerability was reported via the GitHub Bug Bounty program.

Sep 1, 2026
HIGH8.2
CVE-2026-18730
Github Enterprise Server

A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API to send crafted outbound requests to an attacker-controlled host. An unauthenticated endpoint parsed an attacker-supplied cluster configuration and issued gateway-to-agent requests whose HMAC authenticated only a timestamp, not the request path or body. An attacker positioned to intercept the outbound request could capture this token and replay it against privileged management agent endpoints. High-availability deployments were not affected due to a topology restriction. This vulnerability affected GitHub Enterprise Server releases in the 3.17, 3.18, 3.19, 3.20, and 3.21 series and was fixed in versions 3.17.21, 3.18.15, 3.19.12, 3.20.8, and 3.21.6. This vulnerability was reported via the GitHub Bug Bounty program.

Sep 1, 2026
HIGH8.8
CVE-2026-17556
Github Enterprise Server

A path traversal vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to delete arbitrary files and directories on the instance, including the entire user storage directory containing Git LFS objects, release assets, attachments, and avatars. The X-GitHub-Request-Id request header was used without sanitization as a filesystem path segment for the upload buffer directory, so a traversal value pointed the buffer at an arbitrary path and the deferred cleanup routine recursively removed the traversed target. Exploitation required only network reachability to the instance and no authentication, and it worked even when private mode was enabled. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.21.4, 3.20.6, 3.19.10, 3.18.13 and 3.17.19. This vulnerability was reported via the GitHub Bug Bounty program.

Aug 5, 2026
All Github CVEs in 2026
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