CVE-2021-23772

Arbitrary File Write

7.5 HighFix available

This affects all versions of package github.com/kataras/iris; all versions of package github.com/kataras/iris/v12. The unsafe handling of file names during upload using UploadFormFiles method may enable attackers to write to arbitrary locations outside the designated target folder.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: High
Privileges needed: Low
User interaction: None

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: High

Exploit likelihood

1.88%Up 1.0 points since Dec 25, 2021

What each source reports

CVE List Score used 7.5

Arbitrary File Write

Record: CVE-2021-23772
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Updated: 2026-11-02

EUVDEUVD-2022-0626 7.5

Record: EUVD-2022-0626
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Updated: 2026-11-03

GitHub AdvisoriesGHSA-jcxc-rh6w-wf49 7.5

Link Following in Iris

Record: GHSA-jcxc-rh6w-wf49
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-59
Updated: 2026-11-02

NVD 7.5

Record: CVE-2021-23772
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 3.1: 8.8 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 2.0: 6.8 MediumAV:N/AC:M/Au:N/C:P/I:P/A:P
Weakness: CWE-59
Updated: 2026-11-02

OSV 8.8

Record: CVE-2021-23772
CVSS 3.1: 8.8 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Updated: 2026-11-02

OSVGHSA-jcxc-rh6w-wf49 7.5

Link Following in Iris

Record: GHSA-jcxc-rh6w-wf49
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-59
Updated: 2026-11-02

OSVGO-2022-0272 No score

Directory traversal in github.com/kataras/iris and github.com/kataras/iris/v12

The Context.UploadFormFiles function is vulnerable to directory traversal attacks, and can be made to write to arbitrary locations outside the destination directory.

This vulnerability only occurs when built with Go versions prior to 1.17. Go 1.17 and later strip directory paths from filenames returned by "mime/multipart".Part.FileName, which avoids this issue.

Record: GO-2022-0272
Updated: 2026-11-02

Affected products

iris-go iris

Affected packages

Affected packages
Package	Affected	Fixed
`github.com/kataras/iris/v12` Go	before 12.2.0-alpha8	12.2.0-alpha8
`github.com/kataras/iris` Go	through 0.0.2	None known
`github.com/kataras/iris` Go	All versions	None known

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases, published	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2021-23772 is a high vulnerability (CVSS 7.5) in Iris-go Iris, published December 24, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.88%, the 79th percentile. Fixed in github.com/kataras/iris/v12 12.2.0-alpha8.