Description
DBI versions before 1.653 for Perl load arbitrary modules via unvalidated dbm_type and dbm_mldbm attributes in DBD::DBM.
DBD::DBM passes the dbm_type and dbm_mldbm connect attributes to require without checking that the value names a module. require treats a path-shaped string as a literal filename and does not consult @INC, so the attribute chooses the file that Perl loads and runs.
The MLDBM::Serializer:: prefix that DBD::DBM prepends to dbm_mldbm is not a boundary: only the :: separators are rewritten to /, so a value containing / traverses out of the serializer directory. The value is also assigned to $MLDBM::Serializer, which MLDBM requires the same way when it ties the table.
A caller that lets an untrusted party influence either attribute, for example through a DSN fragment or a parameter that selects a storage backend, runs the file-scope code of whatever module the value names.
For example,
my $dsn = "dbi:DBM:f_dir=/var/db;dbm_type=../../Untrusted.pm"
my $dbh = DBI->connect( $dsn );
Note that DBD::Gofer forwards connect attributes to the server side, and DBI::ProxyServer checks only that a DSN starts with a driver prefix.
DBD::DBM passes the dbm_type and dbm_mldbm connect attributes to require without checking that the value names a module. require treats a path-shaped string as a literal filename and does not consult @INC, so the attribute chooses the file that Perl loads and runs.
The MLDBM::Serializer:: prefix that DBD::DBM prepends to dbm_mldbm is not a boundary: only the :: separators are rewritten to /, so a value containing / traverses out of the serializer directory. The value is also assigned to $MLDBM::Serializer, which MLDBM requires the same way when it ties the table.
A caller that lets an untrusted party influence either attribute, for example through a DSN fragment or a parameter that selects a storage backend, runs the file-scope code of whatever module the value names.
For example,
my $dsn = "dbi:DBM:f_dir=/var/db;dbm_type=../../Untrusted.pm"
my $dbh = DBI->connect( $dsn );
Note that DBD::Gofer forwards connect attributes to the server side, and DBI::ProxyServer checks only that a DSN starts with a driver prefix.
Published:
2026-09-19
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis and contextual insights are available on OpenCVE Cloud.
Remediation
Vendor Solution
Upgrade to DBI version 1.653 or later, or apply the upstream patch.
Tracking
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Advisories
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References
History
Sat, 19 Sep 2026 11:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | DBI versions before 1.653 for Perl load arbitrary modules via unvalidated dbm_type and dbm_mldbm attributes in DBD::DBM. DBD::DBM passes the dbm_type and dbm_mldbm connect attributes to require without checking that the value names a module. require treats a path-shaped string as a literal filename and does not consult @INC, so the attribute chooses the file that Perl loads and runs. The MLDBM::Serializer:: prefix that DBD::DBM prepends to dbm_mldbm is not a boundary: only the :: separators are rewritten to /, so a value containing / traverses out of the serializer directory. The value is also assigned to $MLDBM::Serializer, which MLDBM requires the same way when it ties the table. A caller that lets an untrusted party influence either attribute, for example through a DSN fragment or a parameter that selects a storage backend, runs the file-scope code of whatever module the value names. For example, my $dsn = "dbi:DBM:f_dir=/var/db;dbm_type=../../Untrusted.pm" my $dbh = DBI->connect( $dsn ); Note that DBD::Gofer forwards connect attributes to the server side, and DBI::ProxyServer checks only that a DSN starts with a driver prefix. | |
| Title | DBI versions before 1.653 for Perl load arbitrary modules via unvalidated dbm_type and dbm_mldbm attributes in DBD::DBM | |
| Weaknesses | CWE-470 | |
| References |
|
Subscriptions
No data.
Status: PUBLISHED
Assigner: CPANSec
Published:
Updated: 2026-09-19T10:45:10.164Z
Reserved: 2026-08-22T00:39:23.300Z
Link: CVE-2026-78030
No data.
Status : Received
Published: 2026-09-19T11:16:37.667
Modified: 2026-09-19T11:16:37.667
Link: CVE-2026-78030
No data.
OpenCVE Enrichment
No data.
Weaknesses