VulnerabilityAwaiting Analysis

CVE-2026-78222

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.

HIGH 8.7EPSS 0.37%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.37%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 4.0: 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.37% probability · 31th percentile
CISA KEV: Not listed
Weakness: CWE-476
Source: f5sirt@f5.com

References

https://my.f5.com/manage/s/article/K000162603

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.