NGINX ngx_http_rewrite_module vulnerability
Noroxi assessment
Priority: Monitor (action score 37/100)
- Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
- Probability of exploitation in the next 30 days: 3.3% (FIRST EPSS); higher than 88.7% of all records.
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
- Fixed version: F5 NGINX Open Source 1.30.1; azl3 nginx 1.28.3-1 on Azure Linux 3.0 1.28.3-2.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to F5 NGINX Open Source 1.30.1; azl3 nginx 1.28.3-1 on Azure Linux 3.0 1.28.3-2 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when the rewrite directive is followed by a rewrite, if, or set directive and an unnamed Perl-Compatible Regular Expression (PCRE) capture (for example, $1, $2) with a replacement string that includes a question mark (?). An unauthenticated attacker along with conditions beyond its control can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
- BDU:2026-06827
- ALSA-2026:18029
- ALSA-2026:18041
- ALSA-2026:18063
- ALSA-2026:19159
- ALSA-2026:19371
- ALSA-2026:19372
- ALSA-2026:19374
- openSUSE-SU-2026:10796-1
- RHSA-2026:17417
- RHSA-2026:17751
- RHSA-2026:17752
- RHSA-2026:17753
- RHSA-2026:17790
- RHSA-2026:17791
- RHSA-2026:17792
- RHSA-2026:17793
- RHSA-2026:17794
- RHSA-2026:18029
- RHSA-2026:18041
- Published
- May 13, 2026
- Updated
- Sep 10, 2026
- EPSS
- 3.3% · 88th percentile
- CWE
- CWE-122
Report tools
Action score
37
Monitor
Low priority for now.
- CVSS
- 36 / 40 · 9.2 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 3.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · f5
- 8.1
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- Proof of concept exists, no weaponized module
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| f5 | dos | cpe:2.3:a:f5:dos |
| f5 | nginx gateway fabric | cpe:2.3:a:f5:nginx_gateway_fabric |
| f5 | nginx ingress controller | cpe:2.3:a:f5:nginx_ingress_controller |
| f5 | nginx instance manager | cpe:2.3:a:f5:nginx_instance_manager |
| f5 | nginx open source | cpe:2.3:a:f5:nginx_open_source |
| f5 | nginx plus | cpe:2.3:a:f5:nginx_plus |
| f5 | waf | cpe:2.3:a:f5:waf |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- f5 nginx open source0.6.27 and later · up to 1.30.0 inclusive
- f5 nginx plusr32 and later · up to r36 inclusive
Versions reported by the vendor
Affected version ranges reported by the assigning authority (f5). Independent of NVD's CPE analysis and usually ahead of it.
F5 NGINX Open Source
- 1.31.0 and laternot affected · semver
- 0.6.27 and later · before 1.30.1affected · semver
F5 NGINX Plus
- R37 and laternot affected
- R36 and later · before R36 P4affected
- R32 and later · before R32 P6affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:10 | nginx | before 2:1.26.3-6.el10_2.3 | 2:1.26.3-6.el10_2.3 |
| AlmaLinux:10 | nginx-all-modules | before 2:1.26.3-6.el10_2.3 | 2:1.26.3-6.el10_2.3 |
| AlmaLinux:10 | nginx-all-modules | before 2:1.26.3-2.el10_1.2 | 2:1.26.3-2.el10_1.2 |
| AlmaLinux:10 | nginx-core | before 2:1.26.3-6.el10_2.3 | 2:1.26.3-6.el10_2.3 |
| AlmaLinux:10 | nginx-filesystem | before 2:1.26.3-6.el10_2.3 | 2:1.26.3-6.el10_2.3 |
| AlmaLinux:10 | nginx-filesystem | before 2:1.26.3-2.el10_1.2 | 2:1.26.3-2.el10_1.2 |
| AlmaLinux:10 | nginx-mod-devel | before 2:1.26.3-6.el10_2.3 | 2:1.26.3-6.el10_2.3 |
| AlmaLinux:10 | nginx-mod-http-image-filter | before 2:1.26.3-6.el10_2.3 | 2:1.26.3-6.el10_2.3 |
| AlmaLinux:10 | nginx-mod-http-perl | before 2:1.26.3-6.el10_2.3 | 2:1.26.3-6.el10_2.3 |
| AlmaLinux:10 | nginx-mod-http-xslt-filter | before 2:1.26.3-6.el10_2.3 | 2:1.26.3-6.el10_2.3 |
| AlmaLinux:10 | nginx-mod-mail | before 2:1.26.3-6.el10_2.3 | 2:1.26.3-6.el10_2.3 |
| AlmaLinux:10 | nginx-mod-stream | before 2:1.26.3-6.el10_2.3 | 2:1.26.3-6.el10_2.3 |
| AlmaLinux:8 | nginx | before 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 | 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 |
| AlmaLinux:8 | nginx-all-modules | before 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 | 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 |
| AlmaLinux:8 | nginx-filesystem | before 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 | 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 |
| AlmaLinux:8 | nginx-mod-devel | before 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 | 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 |
| AlmaLinux:8 | nginx-mod-http-image-filter | before 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 | 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 |
| AlmaLinux:8 | nginx-mod-http-perl | before 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 | 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 |
| AlmaLinux:8 | nginx-mod-http-xslt-filter | before 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 | 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 |
| AlmaLinux:8 | nginx-mod-mail | before 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 | 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 |
| AlmaLinux:8 | nginx-mod-stream | before 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 | 1:1.24.0-3.module_el8.10.0+4182+ca797750.1.alma.1 |
| AlmaLinux:9 | nginx | before 2:1.20.1-24.el9_7.3.alma.1 | 2:1.20.1-24.el9_7.3.alma.1 |
| AlmaLinux:9 | nginx | before 2:1.20.1-28.el9_8.2.alma.1 | 2:1.20.1-28.el9_8.2.alma.1 |
| AlmaLinux:9 | nginx-all-modules | before 2:1.20.1-24.el9_7.3.alma.1 | 2:1.20.1-24.el9_7.3.alma.1 |
+96
Same product
f5: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-42055NGINX ngx_http_proxy_v2_module and ngx_http_grpc_module vulnerability38Monitor
- CVE-2026-42946NGINX ngx_http_scgi_module and ngx_http_uwsgi_module vulnerability33Monitor
- CVE-2026-40460NGINX ngx_quic_module vulnerability27Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-40701May 13, 2026 · NGINX ngx_http_ssl_module vulnerability25Monitor
- ← EarlierCVE-2026-42934May 13, 2026 · NGINX ngx_http_charset_module vulnerability25Monitor
- Later →CVE-2026-48142Jun 17, 2026 · NGINX ngx_http_charset_module vulnerability25Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| F5 NGINX Open Source | 1.30.1 | Vendor (CNA) |
| azl3 nginx 1.28.3-1 on Azure Linux 3.0 | 1.28.3-2 · CBL-Mariner Releases | Microsoft (MSRC) |
| almalinux:nginx | 2:1.20.1-24.el9_7.3.alma.1 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:nginx-all-modules | 2:1.20.1-24.el9_7.3.alma.1 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:nginx-core | 2:1.20.1-24.el9_7.3.alma.1 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:nginx-filesystem | 2:1.20.1-24.el9_7.3.alma.1 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:nginx-mod-devel | 2:1.20.1-24.el9_7.3.alma.1 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:nginx-mod-http-image-filter | 2:1.20.1-24.el9_7.3.alma.1 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:nginx-mod-http-perl | 2:1.20.1-24.el9_7.3.alma.1 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:nginx-mod-http-xslt-filter | 2:1.20.1-24.el9_7.3.alma.1 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:nginx-mod-mail | 2:1.20.1-24.el9_7.3.alma.1 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:nginx-mod-stream | 2:1.20.1-24.el9_7.3.alma.1 · AlmaLinux:9 | Package registry (OSV) |
| alpine:nginx | 1.26.3-r1 · Alpine:v3.21 | Package registry (OSV) |
| debian:nginx | 1.22.1-9+deb12u7 · Debian:12 | Package registry (OSV) |
| opensuse:nginx | 1.31.0-1.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| red hat:nginx | 0:1.30.1-1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:nginx-all-modules | 0:1.30.1-1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:nginx-core | 0:1.30.1-1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:nginx-core | 1:1.20.1-14.el9_2.6 · Red Hat:rhel_e4s:9.2::appstream | Package registry (OSV) |
| red hat:nginx-core-debuginfo | 1:1.20.1-14.el9_2.6 · Red Hat:rhel_e4s:9.2::appstream | Package registry (OSV) |
| red hat:nginx-debuginfo | 1:1.20.1-14.el9_2.6 · Red Hat:rhel_e4s:9.2::appstream | Package registry (OSV) |
| red hat:nginx-debugsource | 1:1.20.1-14.el9_2.6 · Red Hat:rhel_e4s:9.2::appstream | Package registry (OSV) |
| red hat:nginx-filesystem | 0:1.30.1-1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:nginx-filesystem | 1:1.20.1-14.el9_2.6 · Red Hat:rhel_e4s:9.2::appstream | Package registry (OSV) |
| red hat:nginx-mod-devel | 0:1.30.1-1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:nginx-mod-http-geoip | 0:1.30.1-1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:nginx-mod-http-image-filter | 0:1.30.1-1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:nginx-mod-http-image-filter | 1:1.20.1-14.el9_2.6 · Red Hat:rhel_e4s:9.2::appstream | Package registry (OSV) |
| red hat:nginx-mod-http-image-filter-debuginfo | 1:1.20.1-14.el9_2.6 · Red Hat:rhel_e4s:9.2::appstream | Package registry (OSV) |
| red hat:nginx-mod-http-perl | 0:1.30.1-1.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
+9
Exploit status
Proof of concept available
A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.
Evidence
- Proof-of-concept repository on GitHub ×46
Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.
| Source | Kind | Date |
|---|---|---|
| Proof-of-concept repository on GitHub | stars:34 | 2026-05-14 |
| Proof-of-concept repository on GitHub | stars:15 | 2026-05-14 |
| Proof-of-concept repository on GitHub | stars:1 | 2026-05-14 |
| Proof-of-concept repository on GitHub | stars:64 | 2026-05-14 |
| Proof-of-concept repository on GitHub | stars:3 | 2026-05-14 |
| Proof-of-concept repository on GitHub | stars:24 | 2026-05-14 |
| Proof-of-concept repository on GitHub | stars:2 | 2026-05-14 |
| Proof-of-concept repository on GitHub | stars:0 | 2026-05-14 |
| Proof-of-concept repository on GitHub | stars:19 | 2026-05-15 |
| Proof-of-concept repository on GitHub | stars:1 | 2026-05-15 |
| Proof-of-concept repository on GitHub | stars:1 | 2026-05-15 |
| Proof-of-concept repository on GitHub | stars:4 | 2026-05-15 |
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- First PoCsame day
- TodayOct 24, 2026+164 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- F5 acknowledges Zhenpeng (Leo) Lindepthfirst for bringing this issue to our attention and following the highest standards of coordinated disclosure.finder
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-4205535 days apartNGINX ngx_http_proxy_v2_module and ngx_http_grpc_module vulnerability38Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-26-0241 · May 15, 2026(F5 Networks NGINX Güvenlik Bildirimi)
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- Special conditions such as timing or configuration are required.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- None
- User interaction
- None
- Scope
- X
Weakness class (CWE)
CWE-122 · Heap-based Buffer OverflowCVSS vector
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (19 more)Show less
- my.f5.com/manage/s/article/K000161019
- depthfirst.com/nginx-rift
- access.redhat.com/errata/RHSA-2026:17417
- access.redhat.com/errata/RHSA-2026:17751
- access.redhat.com/errata/RHSA-2026:17752
- access.redhat.com/errata/RHSA-2026:17753
- access.redhat.com/errata/RHSA-2026:17790
- access.redhat.com/errata/RHSA-2026:17791
- access.redhat.com/errata/RHSA-2026:17792
- access.redhat.com/errata/RHSA-2026:17793
- access.redhat.com/errata/RHSA-2026:17794
- access.redhat.com/errata/RHSA-2026:18029
- access.redhat.com/errata/RHSA-2026:18041
- access.redhat.com/errata/RHSA-2026:18063
- access.redhat.com/errata/RHSA-2026:19159
- access.redhat.com/errata/RHSA-2026:19371
- access.redhat.com/errata/RHSA-2026:19372
- access.redhat.com/errata/RHSA-2026:19374
- access.redhat.com/errata/RHSA-2026:20442
Vendor advisories and official records. Exploit/PoC links are deliberately left out.