ikiwiki's web interface does not currently have UI for removing
multiple pages simultaneously, but the remove plugin is robust
against doing so. Use a clearer idiom to make that obvious.
These instances of code similar to OVE-20170111-0001 are not believed
to be exploitable, because defined(), length(), setpassword(),
userinfo_set() and the binary "." operator all have prototypes that
force the relevant argument to be evaluated in scalar context. However,
using a safer idiom makes mistakes less likely.
(cherry picked from commit 69230a2220f673c66b5ab875bfc759b32a241c0d)
Calling CGI::FormBuilder::field with a name argument in list context
returns zero or more user-specified values of the named field, even
if that field was not declared as supporting multiple values.
Passing the result of field as a function parameter counts as list
context. This is the same bad behaviour that is now discouraged
for CGI::param.
In this case we pass the multiple values to CGI::Session::param.
That accessor has six possible calling conventions, of which four are
documented. If an attacker passes (2*n + 1) values for the 'name'
field, for example name=a&name=b&name=c, we end up in one of the
undocumented calling conventions for param:
# equivalent to: (name => 'a', b => 'c')
$session->param('name', 'a', 'b', 'c')
and the 'b' session parameter is unexpectedly set to an
attacker-specified value.
In particular, if an attacker "bob" specifies
name=bob&name=name&name=alice, then authentication is carried out
for "bob" but the CGI::Session ends up containing {name => 'alice'},
an authentication bypass vulnerability.
This vulnerability is tracked as OVE-20170111-0001.
(cherry picked from commit e909eb93f4530a175d622360a8433e833ecf0254)
The Debian security tracker gets timely updates, whereas the official
CVE pages hosted by MITRE tend to show up as "RESERVED" for several
weeks or months after assignment.
openmedi
svetlana@192500fb6a2e2ef8e78d1a08cca64b1bca9833b9
Louis
krqt.kndy@eb44788e4eb202f3e68eeb8ba175d3897c3979a9
vegardv@75ae889e836bda8ce69bc038d8335c398a2f6f40
smcv
me@4eb1b66f86170ba2ff0690b93ad01f46bfc8eac4
Simon McVittie