F5 NGINX JavaScript up to 1.0.0 HTTP Response ngx.fetch denial of service

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k1.43+

Summaryinfo

A vulnerability categorized as problematic has been discovered in F5 NGINX JavaScript up to 1.0.0. The impacted element is the function ngx.fetch of the component HTTP Response. The manipulation results in denial of service. This vulnerability is identified as CVE-2026-78222. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in F5 NGINX JavaScript up to 1.0.0. Affected is the function ngx.fetch of the component HTTP Response. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. CVE summarizes:

A vulnerability exists in NGINX JavaScript where a malformed HTTP response received by ngx.fetch() can crash an NGINX worker when trusted JavaScript reads Response.statusText. Exploitation requires control or influence over the fetched HTTP response. Impact: This vulnerability may allow remote attackers to cause a denial-of-service (DoS) on the NGINX system. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

The advisory is shared for download at my.f5.com. This vulnerability is traded as CVE-2026-78222 since 08/26/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 1.0.1 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

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: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: NGINX JavaScript 1.0.1

Timelineinfo

08/26/2026 CVE reserved
09/02/2026 +7 days Advisory disclosed
09/02/2026 +0 days VulDB entry created
09/02/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: f5.com

Advisory: my.f5.com
Status: Confirmed

CVE: CVE-2026-78222 (🔒)
GCVE (CVE): GCVE-0-2026-78222
GCVE (VulDB): GCVE-100-398196

Entryinfo

Created: 09/02/2026 18:03
Changes: 09/02/2026 18:03 (77)
Complete: 🔍
Cache ID: 216::103

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