CVE-2026-42945 (GCVE-0-2026-42945)
Vulnerability from cvelistv5 – Published: 2026-05-13 14:12 – Updated: 2026-05-14 18:54
VLAI?
Title
NGINX ngx_http_rewrite_module vulnerability
Summary
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, for systems with Address Space Layout Randomization (ASLR ) disabled, code execution is possible. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Severity ?
8.1 (High)
CWE
- CWE-122 - Heap-based Buffer Overflow.
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://my.f5.com/manage/s/article/K000161019 | vendor-advisorypatch |
Impacted products
2 products
| Vendor | Product | Version | |
|---|---|---|---|
| F5 | NGINX Plus |
Unaffected:
R37 , < *
(custom)
Affected: R36 , < R36 P4 (custom) Affected: R32 , < R32 P6 (custom) |
|
| F5 | NGINX Open Source |
Unaffected:
1.31.0 , < *
(semver)
Affected: 0.6.27 , < 1.30.1 (semver) |
Date Public ?
2026-05-13 14:00
Credits
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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