Erlang OTP up to 6.x/[email protected] tftp_file tftp_file.erl path traversal

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k2.59

Summaryinfo

A vulnerability marked as critical has been reported in Erlang OTP up to 6.x/[email protected]. Impacted is an unknown function in the library lib/tftp/src/tftp_file.erl of the component tftp_file. The manipulation leads to path traversal. This vulnerability is traded as CVE-2026-21620. It is possible to initiate the attack remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Erlang OTP up to 6.x/[email protected] and classified as critical. This issue affects an unknown code in the library lib/tftp/src/tftp_file.erl of the component tftp_file. The manipulation with an unknown input leads to a path traversal vulnerability. Using CWE to declare the problem leads to CWE-23. The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as ".." that can resolve to a location that is outside of that directory. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Relative Path Traversal, Improper Isolation or Compartmentalization vulnerability in erlang otp erlang/otp (tftp_file modules), erlang otp inets (tftp_file modules), erlang otp tftp (tftp_file modules) allows Relative Path Traversal. This vulnerability is associated with program files lib/tftp/src/tftp_file.erl, src/tftp_file.Erl. This issue affects otp: from 17.0, from 07b8f441ca711f9812fad9e9115bab3c3aa92f79; otp: from 5.10 before 7.0; otp: from 1.0.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-21620 since 01/01/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1006 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 299721 (Linux Distros Unpatched Vulnerability : CVE-2026-21620), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability. Applying the patch 3970738f687325138eb75f798054fa8960ac354e is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (299721) and CERT Bund (WID-SEC-2026-0473). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • SUSE openSUSE
  • Open Source Erlang/OTP

Productinfo

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Path traversal
CWE: CWE-23 / CWE-22
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 299721
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-21620

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Patch: 3970738f687325138eb75f798054fa8960ac354e

Timelineinfo

01/01/2026 CVE reserved
02/20/2026 +50 days Advisory disclosed
02/20/2026 +0 days VulDB entry created
04/23/2026 +62 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-hmrc-prh3-rpvp
Status: Confirmed

CVE: CVE-2026-21620 (🔒)
GCVE (CVE): GCVE-0-2026-21620
GCVE (VulDB): GCVE-100-347099
CERT Bund: WID-SEC-2026-0473 - Erlang/OTP: Schwachstelle ermöglicht Offenlegung von Informationen

Entryinfo

Created: 02/20/2026 14:56
Updated: 04/23/2026 13:17
Changes: 02/20/2026 14:56 (69), 02/22/2026 04:07 (2), 04/23/2026 13:17 (7)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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