CyberSecBulletin
CVE-2026-15043NVD status: Deferred

DBI::SQL::Nano: Use of Incorrect Operator

CVE-2026-15043 is a critical-severity use of incorrect operator vulnerability in DBI::SQL::Nano from Hmbrand, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 1.651 as the first without the flaw, so updating DBI::SQL::Nano to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.67% chance of exploitation within 30 days, higher than 53% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update DBI::SQL::Nano to 1.651 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
HMBRANDDBI::SQL::Nano1.42 up to, but not including, 1.6511.651

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CISA (ADP).

Official description

DBI::SQL::Nano versions from 1.42 before 1.651 for Perl have inverted <= and >= SQL operators on text. DBI::SQL::Nano, DBI's built-in mini-SQL engine, evaluated WHERE predicates incorrectly in some cases. In the non-numeric string branch of the is_matched method, <= was evaluated using Perl's ge operator, and >= was evaluated using Perl's le operator. SQL::Nano is the fallback query engine for DBI's file-backed drivers (DBD::File, DBD::DBM, CSV-style drivers) whenever SQL::Statement is not installed, and is forced whenever DBI_SQL_NANO=1. Queries over such tables use these predicates directly. The impact depends on the context. Where an application relies on a WHERE clause to filter file-backed data for policy or authorization, an inverted <=/>= comparison silently returns the wrong rows.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use of Incorrect Operator

The product accidentally uses the wrong operator, which changes the logic in security-relevant ways.

More Use of Incorrect Operator vulnerabilities (CWE-480)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Use of Incorrect Operator vulnerabilities

Spotted an error? Tell us.