Multiple format string vulnerabilities in the error reporting functionality in the YAML::LibYAML (aka YAML-LibYAML and perl-YAML-LibYAML) module 0.38 for Perl allow remote attackers to cause a denial of service (process crash) via format string specifiers in a (1) YAML stream to the Load function, (2) YAML node to the load_node function, (3) YAML mapping to the load_mapping function, or (4) YAML sequence to the load_sequence function.
The product uses a function that accepts a format string as an argument, but the format string originates from an external source.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Yaml::libyaml | Ingy | 0.38 (including) | 0.38 (including) |
| Libyaml-libyaml-perl | Ubuntu | devel | * |
| Libyaml-libyaml-perl | Ubuntu | lucid | * |
| Libyaml-libyaml-perl | Ubuntu | maverick | * |
| Libyaml-libyaml-perl | Ubuntu | natty | * |
| Libyaml-libyaml-perl | Ubuntu | oneiric | * |
| Libyaml-libyaml-perl | Ubuntu | precise | * |
| Libyaml-libyaml-perl | Ubuntu | quantal | * |
| Libyaml-libyaml-perl | Ubuntu | raring | * |
| Libyaml-libyaml-perl | Ubuntu | saucy | * |
| Libyaml-libyaml-perl | Ubuntu | upstream | * |
When an attacker can modify an externally-controlled format string, this can lead to buffer overflows, denial of service, or data representation problems. It should be noted that in some circumstances, such as internationalization, the set of format strings is externally controlled by design. If the source of these format strings is trusted (e.g. only contained in library files that are only modifiable by the system administrator), then the external control might not itself pose a vulnerability.