Skip to content
CVE Tracker
  • Newest CVEsPage
  • Recently added to KEVPage
  • Rising exploitation (EPSS)Page
  • Weekly digestPage
  • StatisticsPage
  • WatchlistPage
  • API documentationPage
  • MCP serverPage
  • Data sourcesPage
  • ChangelogPage
  • AboutPage
  • How it's builtPage
Back

CVE-2026-1355

Missing Authorization Check in GitHub Enterprise Server Allows Unauthorized Uploads to Repository Migration Exports

Medium6.0EPSS 0.46%
Published
Updated
Reserved
Assigned by
GitHub_P

Description

A Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to upload unauthorized content to another user’s repository migration export due to a missing authorization check in the repository migration upload endpoint. By supplying the migration identifier, an attacker could overwrite or replace a victim’s migration archive, potentially causing victims to download attacker-controlled repository data during migration restores or automated imports. An attacker would require authentication to the victim's GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.20 and was fixed in versions 3.19.2, 3.18.5, 3.17.11, 3.16.14, 3.15.18, 3.14.23. This vulnerability was reported via the GitHub Bug Bounty program.

Scores

CVSS scores of CVE-2026-1355, by who scored it
Scored byCVSSScoreVector
GitHub_PCNA (assigner)4.0Medium6.0CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:L
NVDNVD · Analyzed4.0Medium6.0CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:L/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
EPSS (exploitation in 30 days)
0.46% · top 60% of all CVEs (6 Nov 2026)
CISA SSVC
Exploitation: none · Automatable: no · Technical impact: partial
Loading the EPSS history…

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.0.

Weakness

Affected products

  • GitHub · Enterprise Server

    • affected 3.19.0 – ≤ 3.19.1
    • affected 3.18.0 – ≤ 3.18.4
    • affected 3.17.0 – ≤ 3.17.10
    • affected 3.16.0 – ≤ 3.16.13
    • affected 3.15.0 – ≤ 3.15.17
    • affected 3.14.0 – ≤ 3.14.22

References (6)

Sources

The same CVE in the primary databases and aggregators, to check against.

Badge for a README or a ticket

CVE-2026-1355 badge
[![CVE-2026-1355](https://trackcve.app/badge/CVE-2026-1355.svg)](https://trackcve.app/cve/CVE-2026-1355)

Record last updated .