CVE-2026-78433

Gitea's web attachment handler skips its cross-repository ownership check for attachments created before 16 January 2026 and checks permissions against the repository named in the request URL instead. An unauthenticated attacker who knows a private attachment's UUID can request it through a public repository's attachment path and retrieve its contents. This can expose issue and pull request attachments or release assets; the random attachment UUID must already be known to the attacker.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://blog.gitea.com/release-of-1.27.3/
https://github.com/go-gitea/gitea/pull/39048
https://github.com/go-gitea/gitea/pull/39077
https://github.com/go-gitea/gitea/releases/tag/v1.27.3
https://github.com/go-gitea/gitea/security/advisories/GHSA-frpv-2xgv-wxpq

Configurations

No configuration.

History

18 Oct 2026, 14:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.9

14 Oct 2026, 15:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 15:17

Updated : 2026-10-18 14:16

NVD link : CVE-2026-78433

Mitre link : CVE-2026-78433

CVE.ORG link : CVE-2026-78433

JSON object : View

Products Affected

No product.

CWE

CWE-284

Improper Access Control

CWE-639

Authorization Bypass Through User-Controlled Key

CWE-863

Incorrect Authorization

CWE-1220

Insufficient Granularity of Access Control

{"id": "CVE-2026-78433", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-78433", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-18T13:35:32.390912Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.9, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 3.6, "exploitabilityScore": 2.2}]}, "affected": [{"source": "88ee5874-cf24-4952-aea0-31affedb7ff2", "affectedData": [{"vendor": "Gitea", "product": "Gitea", "versions": [{"status": "affected", "version": "1.26.0", "versionType": "semver", "lessThanOrEqual": "1.27.2"}], "packageName": "gitea.dev", "defaultStatus": "unaffected"}]}], "published": "2026-10-14T15:17:25.637", "references": [{"url": "https://blog.gitea.com/release-of-1.27.3/", "source": "88ee5874-cf24-4952-aea0-31affedb7ff2"}, {"url": "https://github.com/go-gitea/gitea/pull/39048", "source": "88ee5874-cf24-4952-aea0-31affedb7ff2"}, {"url": "https://github.com/go-gitea/gitea/pull/39077", "source": "88ee5874-cf24-4952-aea0-31affedb7ff2"}, {"url": "https://github.com/go-gitea/gitea/releases/tag/v1.27.3", "source": "88ee5874-cf24-4952-aea0-31affedb7ff2"}, {"url": "https://github.com/go-gitea/gitea/security/advisories/GHSA-frpv-2xgv-wxpq", "source": "88ee5874-cf24-4952-aea0-31affedb7ff2"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "88ee5874-cf24-4952-aea0-31affedb7ff2", "description": [{"lang": "en", "value": "CWE-284"}, {"lang": "en", "value": "CWE-639"}, {"lang": "en", "value": "CWE-863"}, {"lang": "en", "value": "CWE-1220"}]}], "descriptions": [{"lang": "en", "value": "Gitea's web attachment handler skips its cross-repository ownership check for attachments created before 16 January 2026 and checks permissions against the repository named in the request URL instead. An unauthenticated attacker who knows a private attachment's UUID can request it through a public repository's attachment path and retrieve its contents. This can expose issue and pull request attachments or release assets; the random attachment UUID must already be known to the attacker."}], "lastModified": "2026-10-18T14:16:56.500", "sourceIdentifier": "88ee5874-cf24-4952-aea0-31affedb7ff2"}