How severe is CVE-2026-3306?

CVE-2026-3306 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-3306 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-3306?

CVE-2026-3306 affects Github Enterprise Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-3306?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-3306 have an EU (EUVD) identifier?

Yes. CVE-2026-3306 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10742.

When was CVE-2026-3306 published?

CVE-2026-3306 was published on 2026-03-10 and last updated on 2026-06-17.

CVE-2026-3306

CVE-2026-3306 is a medium-severity vulnerability in Github Enterprise Server with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-639.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v4: 5.3
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-10742
Weakness: CWE-639
Affected product: Github Enterprise Server
Published: 2026-03-10
Last modified: 2026-06-17

Description

An improper authorization vulnerability was identified in GitHub Enterprise Server that allowed a user with read access to a repository and write access to a project to modify issue and pull request metadata through the project. When adding an item to a project that already existed, column value updates were applied without verifying the actor's repository write permissions. This vulnerability was reported via the GitHub Bug Bounty program and has been fixed in GitHub Enterprise Server versions 3.14.24, 3.15.19, 3.16.15, 3.17.12, 3.18.6 and 3.19.3.

Frequently asked questions

What is CVE-2026-3306?: An improper authorization vulnerability was identified in GitHub Enterprise Server that allowed a user with read access to a repository and write access to a project to modify issue and pull request metadata through the project. When adding an item to a project that already existed, column value updates were applied without verifying the actor's repository write permissions. This vulnerability was reported via the GitHub Bug Bounty program and has been fixed in GitHub Enterprise Server versions 3.14.24, 3.15.19, 3.16.15, 3.17.12, 3.18.6 and 3.19.3.
How severe is CVE-2026-3306?: CVE-2026-3306 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-3306 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-3306?: CVE-2026-3306 affects Github Enterprise Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-3306?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-3306 have an EU (EUVD) identifier?: Yes. CVE-2026-3306 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10742.
When was CVE-2026-3306 published?: CVE-2026-3306 was published on 2026-03-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*

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