ignore version parsing error

[tarunKoyalwar]

Proposed Changes

• By default version related parsing errors are ignored now
  • Nuclei checks if errors is dsl.ErrParsingArg and ignore if true . in future if want to hide any specific dsl errors returning this error should do the trick
  • closes WRN] [CVE-2019-6799] Malformed version: [7 1] #3983
  • closes [WRN] [CVE-2019-6799] Malformed version: [6.20.35 188 17] #3950

POC

$ echo https://example.com | ./nuclei -t ~/test-templates/comparewarning.yaml -v

                     __     _
   ____  __  _______/ /__  (_)
  / __ \/ / / / ___/ / _ \/ /
 / / / / /_/ / /__/ /  __/ /
/_/ /_/\__,_/\___/_/\___/_/   v2.9.9

		projectdiscovery.io

[INF] Current nuclei version: v2.9.9 (latest)
[INF] Current nuclei-templates version: v9.5.8 (latest)
[INF] New templates added in latest release: 113
[INF] Templates loaded for current scan: 1
[INF] Targets loaded for current scan: 1
[VER] [basic-example] Sent HTTP request to https://example.com
[INF] No results found. Better luck next time!

template

id: basic-example

info:
  name: Test HTTP Template
  author: pdteam
  severity: info

http:
  - method: GET
    path:
      - "{{BaseURL}}"

    matchers:
      - type: dsl
        dsl:
          - compare_versions("GG", '< 4.8.5')

[tarunKoyalwar]

SHOW_DSL_ERRORS env

• since errors may be required in some cases . setting this env variable will show ignored dsl errors

$ SHOW_DSL_ERRORS=true ./nuclei -u https://example.com -t ~/test-templates/comparewarning.yaml -v

                     __     _
   ____  __  _______/ /__  (_)
  / __ \/ / / / ___/ / _ \/ /
 / / / / /_/ / /__/ /  __/ /
/_/ /_/\__,_/\___/_/\___/_/   v2.9.9

		projectdiscovery.io

[INF] Current nuclei version: v2.9.9 (latest)
[INF] Current nuclei-templates version: v9.5.8 (latest)
[INF] New templates added in latest release: 113
[INF] Templates loaded for current scan: 1
[INF] Targets loaded for current scan: 1
[VER] [basic-example] Sent HTTP request to https://example.com
[WRN] [basic-example] error parsing argument value
[INF] No results found. Better luck next time!

[Mzack9999]

Implementation: lgtm!
I'd recommend to also add:

• Integration Tests
• Update docs if necessary with new ENV variable flag explanation (I'm not sure if we have already a section for this)

[tarunKoyalwar]

depends on projectdiscovery/dsl#68

[tarunKoyalwar]

@Mzack9999 @ehsandeep , created new file DEBUG.md to track all debugging options available in nuclei https://github.com/projectdiscovery/nuclei/blob/issue-3950-dsl-warning/DEBUG.md

i think it will also be helpful for other teams