Fix panic on malformed LDAP responses#586
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cpuschma merged 1 commit intogo-ldap:masterfrom Apr 4, 2026
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Six operations (Add, Del, Compare, Modify, ModifyDN, PasswordModify) access packet.Children[1] without bounds checking. A malformed BER response with fewer than 2 children causes a panic (index out of range). Add len(packet.Children) < 2 guard in all affected functions, returning a descriptive error instead of panicking. Fixes #585
cpuschma
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Apr 4, 2026
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Problem
Six operations (
Add,Del,Compare,Modify,ModifyDN,PasswordModify) accesspacket.Children[1]without bounds checking. A malformed BER response with fewer than 2 children causes a panic (index out of range).Issue #453 previously fixed
GetLDAPErrorfor the same class of bug, but these individual callers were never patched.Fixes #585
Solution
Add
len(packet.Children) < 2guard before accessingpacket.Children[1]in all seven affected call sites across six files:v3/add.go—Add()v3/del.go—Del()v3/compare.go—Compare()v3/modify.go—Modify()andModifyWithResult()v3/moddn.go—ModifyDN()v3/passwdmodify.go—PasswordModify()Each now returns a descriptive error (
"ldap: malformed response: expected at least 2 children, got N") instead of panicking.Testing
The fix is purely defensive — existing tests should pass unchanged. A malformed packet with 0 or 1 children will now return an error instead of crashing.