JavaScript garbage-collection hazard audit


Igor  Bukanov  has audited the JavaScript engine for routines that use
temporary variables not protected against garbage-collection. If malicious
content could cause garbage-collection to run during the lifetime of these
temporaries  then the original routine would end up operating on freed
memory.

The  risk  appears  remote,  but  this type of memory corruption could
potentially be used by an attacker to run arbitrary code including the
installation of malware.

Note: Thunderbird shares the JavaScript engine with Firefox and could be
vulnerable if JavaScript were to be enabled in mail. This is not the default
setting and we strongly discourage users from running JavaScript in mail.

Workaround

Upgrade to the fixed versions. Do not enable JavaScript in Thunderbird or
Mozilla Suite mail.

References

[1]https://bugzilla.mozilla.org/show_bug.cgi?id=311497
[2]https://bugzilla.mozilla.org/show_bug.cgi?id=311792
[3]https://bugzilla.mozilla.org/show_bug.cgi?id=312278
[4]https://bugzilla.mozilla.org/show_bug.cgi?id=313276
[5]https://bugzilla.mozilla.org/show_bug.cgi?id=313479
[6]https://bugzilla.mozilla.org/show_bug.cgi?id=313630
[7]https://bugzilla.mozilla.org/show_bug.cgi?id=313726
[8]https://bugzilla.mozilla.org/show_bug.cgi?id=313763
[9]https://bugzilla.mozilla.org/show_bug.cgi?id=313938
[10]https://bugzilla.mozilla.org/show_bug.cgi?id=325269


This issue also affects FC4