CVE Intelligence
Medium Logic error

CVE-2026-0421 — Unchecked Return Value in Lenovo ThinkPad L13 Gen 6 2 in 1 BIOS

A potential vulnerability was reported in the BIOS of L13 Gen 6, L13 Gen 6 2-in-1, L14 Gen 6, and L16 Gen 2 ThinkPads which could result in Secure Boot being disabled even when configured as “On” in the BIOS setup menu. This issue only affects systems where Secure Boot is set to User Mode.

Published Jan 14, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: lenovo

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.2% (30-day exploitation probability)+1
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.16%
ahead of 5% of scored CVEs · Oct 14, 2026
Affects
Lenovo
ThinkPad L13 Gen 6 2 in 1 BIOS and 3 more
CVSS base
6.5
Medium · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Lenovo ThinkPad L13 Gen 6 2 in 1 BIOS, Lenovo ThinkPad L13 Gen 6 BIOS, Lenovo ThinkPad L14 Gen 6 BIOS…).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
  4. Search available logs for exploit probes matching the vulnerability class (logic error), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Lenovo ThinkPad L13 Gen 6 2 in 1 BIOS < 1.10 Vulnerable CVE Program (cve.org) e CISA ADP
Lenovo ThinkPad L13 Gen 6 BIOS < 1.10 Vulnerable CVE Program (cve.org) e CISA ADP
Lenovo ThinkPad L14 Gen 6 BIOS < 1.06 Vulnerable CVE Program (cve.org) e CISA ADP
Lenovo ThinkPad L16 Gen 2 BIOS < 1.06 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Local
Attack complexity
Low
Privileges required
High
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
7.0 CVSS 4.0 High — — psirt@lenovo.com via NIST National Vulnerability Database
7.0 CVSS 4.0 High — — lenovo via CVE Program (cve.org) e CISA ADP
6.5 CVSS 3.1 Medium 0.6 5.9 psirt@lenovo.com via NIST National Vulnerability Database
6.5 CVSS 3.1 Medium — — lenovo via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H (score shown at the top: psirt@lenovo.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-252 · Unchecked Return Value

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.16%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
endpoint telemetry (EDR)

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · lenovo/thinkpad l13 gen 6 bios, lenovo/thinkpad l13 gen 6 2 in 1 bios, lenovo/thinkpad l14 gen 6 bios, lenovo/thinkpad l
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • CVSS changed · 6.5
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Deferred
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    Jan 14, 2026 · lenovo

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

Elsewhere on this site

Lenovo
every CVE for this vendor
Logic error
same class
CWE-252
other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-0421 is "Unchecked Return Value in Lenovo ThinkPad L13 Gen 6 2 in 1 BIOS", rated Medium. It affects ThinkPad L13 Gen 6 2 in 1 BIOS (Lenovo); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.5 describes technical severity. EPSS 0.16% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

Comments

Moderated technical discussion. Read the community guidelines.

No comments yet.

Sign in or create an account to comment and suggest corrections.