CVE-2026-27784
The 32-bit implementation of NGINX Open Source has a vulnerability in the ngx_http_mp4_module module, which might allow an attacker to over-read or over-write NGINX worker memory resulting in its termination, using a specially crafted MP4 file.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.03%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
The 32-bit implementation of NGINX Open Source has a vulnerability in the ngx_http_mp4_module module, which might allow an attacker to over-read or over-write NGINX worker memory resulting in its termination, using a specially crafted MP4 file. The issue only affects 32-bit NGINX Open Source if it is built with the ngx_http_mp4_module module and the mp4 directive is used in the configuration file. Additionally, the attack is possible only if an attacker can trigger the processing of a specially crafted MP4 file with the ngx_http_mp4_module module. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
- CVSS 4.0
- 8.5 HIGHCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/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
- 1.03% probability · 62th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-190
- Affected
- f5/nginx open source
- Source
- f5sirt@f5.com
References
- https://my.f5.com/manage/s/article/K000160364Mitigation, Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:10065
- https://access.redhat.com/errata/RHSA-2026:13634
- https://access.redhat.com/errata/RHSA-2026:13680
- https://access.redhat.com/errata/RHSA-2026:13839
- https://access.redhat.com/errata/RHSA-2026:14836
- https://access.redhat.com/errata/RHSA-2026:15942
- https://access.redhat.com/errata/RHSA-2026:15943
- https://access.redhat.com/errata/RHSA-2026:15945
- https://access.redhat.com/errata/RHSA-2026:15966
- https://access.redhat.com/errata/RHSA-2026:6906
- https://access.redhat.com/errata/RHSA-2026:6907
- https://access.redhat.com/errata/RHSA-2026:6923
- https://access.redhat.com/errata/RHSA-2026:7002
- https://access.redhat.com/errata/RHSA-2026:7343
- https://access.redhat.com/errata/RHSA-2026:8346
- https://access.redhat.com/security/cve/CVE-2026-27784
- https://bugzilla.redhat.com/show_bug.cgi?id=2450785
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27784.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.