F5 NGINX Open Source/NGINX Plus prior 1.29.5 Transport Layer Security acceptance of extraneous untrusted data with trusted data

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in F5 NGINX Open Source and NGINX Plus. This issue affects some unknown processing of the component Transport Layer Security. This manipulation causes acceptance of extraneous untrusted data with trusted data. The identification of this vulnerability is CVE-2026-1642. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in F5 NGINX Open Source and NGINX Plus. Affected by this vulnerability is an unknown functionality of the component Transport Layer Security. The manipulation with an unknown input leads to a acceptance of extraneous untrusted data with trusted data vulnerability. The CWE definition for the vulnerability is CWE-349. The product, when processing trusted data, accepts any untrusted data that is also included with the trusted data, treating the untrusted data as if it were trusted. As an impact it is known to affect integrity. The summary by CVE is:

A vulnerability exists in NGINX OSS and NGINX Plus when configured to proxy to upstream Transport Layer Security (TLS) servers. An attacker with a man-in-the-middle (MITM) position on the upstream server side—along with conditions beyond the attacker's control—may be able to inject plain text data into the response from an upstream proxied server.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

It is possible to read the advisory at my.f5.com. This vulnerability is known as CVE-2026-1642 since 01/29/2026. The exploitation appears to be difficult. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 03/05/2026).

The vulnerability scanner Nessus provides a plugin with the ID 297957 (Linux Distros Unpatched Vulnerability : CVE-2026-1642), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.29.5 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (297957) and CERT Bund (WID-SEC-2026-0309). Be aware that VulDB is the high quality source for vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • Oracle Linux
  • RESF Rocky Linux
  • NGINX NGINX
  • NGINX NGINX Plus

Productinfo

Type

Vendor

Name

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: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.9
CNA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Acceptance of extraneous untrusted data with trusted data
CWE: CWE-349
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: 297957
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-1642

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: NGINX Open Source/NGINX Plus 1.29.5

Timelineinfo

01/29/2026 CVE reserved
02/04/2026 +6 days Advisory disclosed
02/04/2026 +0 days VulDB entry created
03/05/2026 +29 days VulDB entry last update

Sourcesinfo

Vendor: f5.com

Advisory: K000159824
Status: Confirmed

CVE: CVE-2026-1642 (🔒)
GCVE (CVE): GCVE-0-2026-1642
GCVE (VulDB): GCVE-100-344359
CERT Bund: WID-SEC-2026-0309 - NGINX OSS und NGINX Plus: Schwachstelle ermöglicht Manipulation von Dateien

Entryinfo

Created: 02/04/2026 18:33
Updated: 03/05/2026 21:53
Changes: 02/04/2026 18:33 (75), 02/05/2026 11:21 (7), 02/05/2026 16:39 (2), 03/05/2026 21:53 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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