CVE-2026-42945 | Vulnerability Intelligence

Stored catalog record

Source record retrieved 2026-10-28T10:24:56.624221+00:00. Scheduled imports handle updates; this page does not assert that the provider was queried just now.

Vulnerability overview

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.

Patch review priority

Elevated predicted exploitation

EPSS probability is at least 10%; this is a published triage threshold, not a combined risk score.

FIRST EPSS: 68.05% · percentile 99.3 · score date 2026-10-27.

EPSS estimates probability of exploitation in the next 30 days. It does not measure your exposure or prove exploitation. The elevated threshold is 10%; CISA KEV takes precedence. About FIRST EPSS ↗

Severity and scoring

CVSS score: 9.2 · CRITICAL
CVSS version: 4.0
CVSS 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
Weaknesses: CWE-122, CWE-131

CVSS measures technical severity; it does not establish whether this vulnerability is being exploited in your environment.

Known exploitation and remediation

Not listed in the CISA catalog retrieved for this record. This does not establish that exploitation has not occurred.

Verify affected versions and patch availability in the vendor advisory before making changes.

Affected products and versions

cpe:2.3:a:f5:dos:*:*:*:*:*:nginx:*:*
From (inclusive): 4.3.0
Through (inclusive): 4.7.0
cpe:2.3:a:f5:dos:4.8.0:*:*:*:*:nginx:*:*
cpe:2.3:a:f5:nginx_gateway_fabric:*:*:*:*:*:*:*:*
From (inclusive): 1.3.0
Through (inclusive): 1.6.2
cpe:2.3:a:f5:nginx_gateway_fabric:*:*:*:*:*:*:*:*
From (inclusive): 2.0.0
Through (inclusive): 2.5.1
cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:*
From (inclusive): 3.5.0
Through (inclusive): 3.7.2
cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:*
From (inclusive): 4.0.0
Through (inclusive): 4.0.1
cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:*
From (inclusive): 5.0.0
Through (inclusive): 5.4.1
cpe:2.3:a:f5:nginx_instance_manager:*:*:*:*:*:*:*:*
From (inclusive): 2.16.0
Through (inclusive): 2.21.1
cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:*
From (inclusive): 0.6.27
Through (inclusive): 1.30.0
cpe:2.3:a:f5:nginx_plus:*:*:*:*:*:*:*:*
From (inclusive): r32
Through (inclusive): r36
cpe:2.3:a:f5:waf:*:*:*:*:*:nginx:*:*
From (inclusive): 4.9.0
Through (inclusive): 4.16.0
cpe:2.3:a:f5:waf:*:*:*:*:*:nginx:*:*
From (inclusive): 5.1.0
Through (inclusive): 5.8.0
cpe:2.3:a:f5:waf:*:*:*:*:*:nginx:*:*
From (inclusive): 5.9.0
Through (inclusive): 5.12.1

These are NVD CPE applicability entries. Some products depend on configuration conditions; consult the official record to confirm applicability.

Advisories and references

Explore official sources

Read the official NVD record ↗

Explore the CISA catalog ↗

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