F5 NGINX Plus/NGINX Open Source Response Header out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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3.6$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in F5 NGINX Plus and NGINX Open Source. This issue affects some unknown processing of the component Response Header Handler. This manipulation causes out-of-bounds. The identification of this vulnerability is CVE-2025-53859. 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 F5 NGINX Plus and NGINX Open Source (the affected version is unknown). It has been declared as problematic. Affected by this vulnerability is an unknown code of the component Response Header Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality. The summary by CVE is:

NGINX Open Source and NGINX Plus have a vulnerability in the ngx_mail_smtp_module that might allow an unauthenticated attacker to over-read NGINX SMTP authentication process memory; as a result, the server side may leak arbitrary bytes sent in a request to the authentication server. This issue happens during the NGINX SMTP authentication process and requires the attacker to make preparations against the target system to extract the leaked data. The issue affects NGINX only if (1) it is built with the ngx_mail_smtp_module, (2) the smtp_auth directive is configured with method "none," and (3) the authentication server returns the "Auth-Wait" response header. 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-2025-53859 since 07/29/2025. 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 vulnerability scanner Nessus provides a plugin with the ID 253588 (nginx 0.7.22 < 1.29.1 Information Disclosure), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (253588) and CERT Bund (WID-SEC-2025-1817). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Amazon Linux 2
  • Fedora Linux
  • Ubuntu Linux
  • SUSE Linux
  • SUSE openSUSE
  • 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: 3.7
VulDB Meta Temp Score: 3.7

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

CNA Base Score: 3.7
CNA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
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: 253588
Nessus Name: nginx 0.7.22 < 1.29.1 Information Disclosure

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

07/29/2025 CVE reserved
08/13/2025 +15 days Advisory disclosed
08/13/2025 +0 days VulDB entry created
01/03/2026 +143 days VulDB entry last update

Sourcesinfo

Vendor: f5.com

Advisory: K000152786
Status: Confirmed

CVE: CVE-2025-53859 (🔒)
GCVE (CVE): GCVE-0-2025-53859
GCVE (VulDB): GCVE-100-319939
CERT Bund: WID-SEC-2025-1817 - NGINX: Schwachstelle erm&ouml;glicht Offenlegung von Informationen

Entryinfo

Created: 08/13/2025 17:52
Updated: 01/03/2026 16:15
Changes: 08/13/2025 17:52 (75), 08/23/2025 19:43 (2), 10/22/2025 04:09 (1), 01/03/2026 16:15 (7)
Complete: 🔍
Cache ID: 216::103

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

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