Coraza: Silent argument drop at ArgumentLimit allows bypass of ARGS-targeted rules via parameter flooding

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.2 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:L

EPSS

• CVE-2026-41510: 0.38% estimated exploitation activity in the next 30 days; percentile 31.81 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Root Cause File: internal/corazawaf/transaction.go, lines 770–808 (since commit 2fd87b89, PR #812, 2023-06-14) AddGetRequestArgument, AddPostRequestArgument, and AddPathRequestArgument silently return once the per-collection argument count reaches WAF.ArgumentLimit (default 1000, see internal/corazawaf/waf.go:346). No error variable is set, no transaction flag is raised, and no rule can observe that a drop occurred. Worse, ExtractGetArguments (transaction.go:761) iterates the map[string][]string returned by urlutil.ParseQuery: Because Go randomizes map iteration order, which of the caller-supplied arguments survive the limit is non-deterministic. An attacker can pad the URI with filler arguments; any one of them — including the malicious payload — may be the one silently discarded, and therefore invisible to every SecRule targeting ARGS, ARGSGET, or ARGSNAMES. Secondary finding — POST urlencoded processor bypasses the cap entirely internal/bodyprocessors/urlencoded.go:29 populates…

Published by the source

6 Oct 2026, 20:38 UTC

Last modified by the source

20 Oct 2026, 00:45 UTC

Source last checked

26 Oct 2026, 15:29 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-6r3q-mjv7-xr8m

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GO-2026-6668

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-6r3q-mjv7-xr8m

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# Patch Next advisory brief: CVE-2026-41510

Advisory: Coraza: Silent argument drop at ArgumentLimit allows bypass of ARGS-targeted rules via parameter flooding
IDs: CVE-2026-41510, GHSA-6r3q-mjv7-xr8m
Record: https://patchnext.com/advisories/cve-2026-41510 (revision 3, source checked 26 Oct 2026, 15:29 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.2)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Partial vendor fix; fixed versions by package: github.com/corazawaf/coraza/v3 3.8.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/corazawaf/coraza/v3: affected >= 3.0.0, < 3.8.1; fixed in 3.8.1
- Go github.com/corazawaf/coraza: affected every version
- Go github.com/corazawaf/coraza/v2: affected every version

## Suggested inspection (read-only)
- Go github.com/corazawaf/coraza/v3: check the installed version with your package manager.
- Go github.com/corazawaf/coraza: check the installed version with your package manager.
- Go github.com/corazawaf/coraza/v2: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/corazawaf/coraza/v3, github.com/corazawaf/coraza, github.com/corazawaf/coraza/v2.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GO-2026-6668 (OSV record GO-2026-6668 lists affected ranges: Go github.com/corazawaf/coraza >=0; Go github.com/corazawaf/coraza/v2 >=0; Go github.com/corazawaf/coraza/v3 >=3.0.0 <3.8.1 (fixed))
- Verified: https://osv.dev/vulnerability/GHSA-6r3q-mjv7-xr8m (OSV record GHSA-6r3q-mjv7-xr8m lists affected ranges: Go github.com/corazawaf/coraza/v3 >=3.0.0 <3.8.1 (fixed))
- Verified: https://github.com/advisories/GHSA-6r3q-mjv7-xr8m (GitHub-reviewed advisory GHSA-6r3q-mjv7-xr8m lists affected ranges: Go github.com/corazawaf/coraza/v3 >=3.0.0 <3.8.1)

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