panic: interface conversion: interface {} is nil, not string [recovered]

[geeknik]

Nuclei version:

Version: v3.2.2
Operating System: linux
Architecture: amd64
Go Version: go1.21.8
Compiler: gc
File "/root/.config/nuclei/config.yaml" Read => Ok
File "/root/.config/nuclei/config.yaml" Write => Ok
File "/root/.config/nuclei/.nuclei-ignore" Read => Ok
File "/root/.config/nuclei/.nuclei-ignore" Write => Ok
File "/root/.bbot/tools/nuclei-templates/.checksum" Read => Ok
File "/root/.bbot/tools/nuclei-templates/.checksum" Write => Ok
IPv4 connectivity to scanme.sh:80 => Ok
IPv6 connectivity to scanme.sh:80 => Ko (dial tcp6 [2400:6180:0:d0::91:1001]:80: connect: network is unreachable)
IPv4 UDP connectivity to scanme.sh:53 => Ok

Current Behavior:

panic: interface conversion: interface {} is nil, not string [recovered]
	panic: interface conversion: interface {} is nil, not string [recovered]
	panic: interface conversion: interface {} is nil, not string [recovered]
	panic: interface conversion: interface {} is nil, not string

goroutine 1 [running]:
gopkg.in/yaml%2ev2.handleErr(0xc000c8eb60)
	gopkg.in/yaml.v2@v2.4.0/yaml.go:249 +0x6d
panic({0x2614840?, 0xc0010e1650?})
	runtime/panic.go:914 +0x21f
gopkg.in/yaml%2ev2.handleErr(0xc000c8e840)
	gopkg.in/yaml.v2@v2.4.0/yaml.go:249 +0x6d
panic({0x2614840?, 0xc0010e1650?})
	runtime/panic.go:914 +0x21f
gopkg.in/yaml%2ev2.handleErr(0xc000c8e040)
	gopkg.in/yaml.v2@v2.4.0/yaml.go:249 +0x6d
panic({0x2614840?, 0xc0010e1650?})
	runtime/panic.go:914 +0x21f
github.com/projectdiscovery/nuclei/v3/pkg/utils.(*InsertionOrderedStringMap).UnmarshalYAML(0xc002e43540, 0xc00234da00)
	github.com/projectdiscovery/nuclei/v3/pkg/utils/insertion_ordered_map.go:43 +0x26c
gopkg.in/yaml%2ev2.(*decoder).callUnmarshaler(0xc000e45a40, 0xc00236f810, {0x7f3406f55e50, 0xc002e43540})
	gopkg.in/yaml.v2@v2.4.0/decode.go:270 +0x94
gopkg.in/yaml%2ev2.(*decoder).prepare(0xc0029873a0?, 0xc00236f810, {0x2773600?, 0xc002e43540?, 0xc000c8dff8?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:313 +0x245
gopkg.in/yaml%2ev2.(*decoder).unmarshal(0xc000e45a40, 0xc00236f810, {0x2773600?, 0xc002e43540?, 0xc000c8e220?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:364 +0x13b
gopkg.in/yaml%2ev2.(*decoder).callUnmarshaler.func1({0x2773600?, 0xc002e43540?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:272 +0xe5
github.com/projectdiscovery/nuclei/v3/pkg/protocols/common/variables.(*Variable).UnmarshalYAML(0xc002e43538, 0xc002e43538?)
	github.com/projectdiscovery/nuclei/v3/pkg/protocols/common/variables/variables.go:36 +0x6d
gopkg.in/yaml%2ev2.(*decoder).callUnmarshaler(0xc000e45a40, 0xc00236f810, {0x7f3406f55e30, 0xc002e43538})
	gopkg.in/yaml.v2@v2.4.0/decode.go:270 +0x94
gopkg.in/yaml%2ev2.(*decoder).prepare(0x41638c?, 0xc00236f810, {0x279bd00?, 0xc002e43538?, 0xf100000000000098?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:313 +0x245
gopkg.in/yaml%2ev2.(*decoder).unmarshal(0xc000e45a40, 0xc00236f810, {0x279bd00?, 0xc002e43538?, 0x0?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:364 +0x13b
gopkg.in/yaml%2ev2.(*decoder).mappingStruct(0xc000e45a40, 0xc00236f180, {0x29e15a0?, 0xc002e43340?, 0x121a1c5?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:767 +0xe4b
gopkg.in/yaml%2ev2.(*decoder).mapping(0xf?, 0xc00236f180?, {0x29e15a0?, 0xc002e43340?, 0x0?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:626 +0x470
gopkg.in/yaml%2ev2.(*decoder).unmarshal(0xc000e45a40, 0xc00236f180, {0x2438f20?, 0xc002e43340?, 0x288?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:372 +0x1a5
gopkg.in/yaml%2ev2.(*decoder).callUnmarshaler.func1({0x2438f20?, 0xc002e43340?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:272 +0xe5
github.com/projectdiscovery/nuclei/v3/pkg/templates.(*Template).UnmarshalYAML(0xc002e42dc0, 0xc00234d9c0)
	github.com/projectdiscovery/nuclei/v3/pkg/templates/templates.go:316 +0x52
gopkg.in/yaml%2ev2.(*decoder).callUnmarshaler(0xc000e45a40, 0xc00236f180, {0x7f340703a730, 0xc002e42dc0})
	gopkg.in/yaml.v2@v2.4.0/decode.go:270 +0x94
gopkg.in/yaml%2ev2.(*decoder).prepare(0xc000c8ea01?, 0xc00236f180, {0x29e12a0?, 0xc002e42dc0?, 0xc003e0f5d8?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:313 +0x245
gopkg.in/yaml%2ev2.(*decoder).unmarshal(0xc000e45a40, 0xc00236f180, {0x29e12a0?, 0xc002e42dc0?, 0x120032b?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:364 +0x13b
gopkg.in/yaml%2ev2.(*decoder).document(...)
	gopkg.in/yaml.v2@v2.4.0/decode.go:384
gopkg.in/yaml%2ev2.(*decoder).unmarshal(0x294ab80?, 0xc002e42dc0?, {0x29e12a0?, 0xc002e42dc0?, 0x410785?})
	gopkg.in/yaml.v2@v2.4.0/decode.go:360 +0x110
gopkg.in/yaml%2ev2.unmarshal({0xc002b45180, 0x289, 0x380}, {0x294ab80, 0xc002e42dc0}, 0x0)
	gopkg.in/yaml.v2@v2.4.0/yaml.go:148 +0x39c
gopkg.in/yaml%2ev2.Unmarshal(...)
	gopkg.in/yaml.v2@v2.4.0/yaml.go:81
github.com/projectdiscovery/nuclei/v3/pkg/templates.parseTemplate({_, _, _}, {{0x0, 0x0}, {0xc002791740, 0x33}, {{0x0, 0x0}, {{0x0, ...}}, ...}, ...})
	github.com/projectdiscovery/nuclei/v3/pkg/templates/compile.go:321 +0x125
github.com/projectdiscovery/nuclei/v3/pkg/templates.ParseTemplateFromReader({_, _}, {_, _}, {{0x0, 0x0}, {0xc002791740, 0x33}, {{0x0, 0x0}, ...}, ...})
	github.com/projectdiscovery/nuclei/v3/pkg/templates/compile.go:266 +0x4f8
github.com/projectdiscovery/nuclei/v3/pkg/templates.Parse({_, _}, {_, _}, {{0x0, 0x0}, {0x0, 0x0}, {{0x0, 0x0}, ...}, ...})
	github.com/projectdiscovery/nuclei/v3/pkg/templates/compile.go:78 +0x4f0
github.com/projectdiscovery/nuclei/v3/pkg/catalog/loader.(*Store).areWorkflowOrTemplatesValid(0xc000e20090, 0xc000c8ff18?, 0x0, 0x31f6b30)
	github.com/projectdiscovery/nuclei/v3/pkg/catalog/loader/loader.go:303 +0x1ab
github.com/projectdiscovery/nuclei/v3/pkg/catalog/loader.(*Store).areTemplatesValid(...)
	github.com/projectdiscovery/nuclei/v3/pkg/catalog/loader/loader.go:286
github.com/projectdiscovery/nuclei/v3/pkg/catalog/loader.(*Store).ValidateTemplates(0xc000e20090)
	github.com/projectdiscovery/nuclei/v3/pkg/catalog/loader/loader.go:272 +0x34f
github.com/projectdiscovery/nuclei/v3/internal/runner.(*Runner).RunEnumeration(0xc0003f82a0)
	github.com/projectdiscovery/nuclei/v3/internal/runner/runner.go:489 +0x1317
main.main()
	./main.go:170 +0x665

Expected Behavior:

No crash.

Steps To Reproduce:

1. go install -v github.com/xm1k3/cent@latest && cent
2. nuclei -t cent-nuclei-templates/ -validate

Anything else:

🕵🏻