Launcher states crash of 13w36b and newer is modded

Confirmed.

Is this because there is no suspicious class line?

13w36b, 13w37a, 13w37b

Minecraft Version: 13w37b
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_40, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 685578072 bytes (653 MB) / 980942848 bytes (935 MB) up to 980942848 bytes (935 MB)
	JVM Flags: 3 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -Xms1G
	AABB Pool Size: 14355 (803880 bytes; 0 MB) allocated, 2 (112 bytes; 0 MB) used
	IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
	Launched Version: 13w37b
	LWJGL: 2.9.0
	OpenGL: AMD Radeon HD 6700 Series GL version 4.2.12217 Compatibility Profile Context 12.104.0.0, ATI Technologies Inc.
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: []
	Current Language: Deutsch (Deutschland)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 912 (51072 bytes; 0 MB) allocated, 12 (672 bytes; 0 MB) used

13w36a

Minecraft Version: 13w36a
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_40, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 734090592 bytes (700 MB) / 1029701632 bytes (982 MB) up to 1029701632 bytes (982 MB)
	JVM Flags: 3 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -Xms1G
	AABB Pool Size: 938 (52528 bytes; 0 MB) allocated, 2 (112 bytes; 0 MB) used
	Suspicious classes: [com.ibm.icu.text.ArabicShapingException], [gnu.trove.TIntCollection], [gnu.trove.impl.HashFunctions, PrimeFinder], [gnu.trove.impl.hash.THash, TPrimitiveHash, TIntIntHash], [gnu.trove.iterator.TIterator, TAdvancingIterator, TIntIntIterator], [gnu.trove.map.TIntIntMap], [gnu.trove.map.hash.TIntIntHashMap], [gnu.trove.procedure.TIntIntProcedure], [gnu.trove.set.TIntSet]
	IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
	Launched Version: 13w36a
	LWJGL: 2.9.0
	OpenGL: AMD Radeon HD 6700 Series GL version 4.2.12217 Compatibility Profile Context 12.104.0.0, ATI Technologies Inc.
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: []
	Current Language: Deutsch (Deutschland)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 1675 (93800 bytes; 0 MB) allocated, 14 (784 bytes; 0 MB) used

[Mojang] Dinnerbone (Nathan Adams) in MC-29497:

Suspicious Classes is removed in the next snapshot.

Well....

Still an issue as of Launcher version 1.2.4 / Minecraft version 13w38a.

this happens to me too, who else because I was just opening an anvil to combine to almost broken gold swords and it crashed and said it was modded. I was running 13w39b.

🙂

Please reopen. Happens again in 14w30b.

That is MC-63288.