NVD / CVE Program· CNA GitHub_M

CVE-2026-85995: Notepad++: Authenticode verification bypass allows modified updater execution

Noroxi assessment

Priority: Monitor (action score 29/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.12% (FIRST EPSS).
Someone with local access to the system can trigger it. A low-privileged account is enough. A user must open a link or visit a page. No special conditions are required; it is repeatable.
Fixed version: notepad-plus-plus notepad-plus-plus 8.9.8.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to notepad-plus-plus notepad-plus-plus 8.9.8 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Notepad++ is a free and open-source source code editor. From 8.9.7 until 8.9.8, the Notepad++ updater and signature verification path can accept a modified GUP.exe file whose embedded certificate metadata remains present even though its Authenticode digest is invalid. An attacker who can replace or plant the updater-related file can cause Notepad++ to launch attacker-modified code when a user triggers the updater path, but the issue does not provide remote code execution by itself. This issue is fixed in version 8.9.8.

HighCVSS 7.3 · v3.1—No exploit Fix available

EUVD-2026-84575

Published: Sep 22, 2026
Updated: Sep 23, 2026
EPSS: 0.1% · 2th percentile
CWE: CWE-347

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 29 / 40 · 7.3 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.1%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · GitHub_M: 7.3; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

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Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

notepad-plus-plus notepad-plus-plus
- < 8.9.8affected

Same product

notepad-plus-plus: all records

Other highest-scoring records for the same primary product.

CVE-2026-85279Notepad++: Stack Buffer Overflow in Plugin Lexer Loading via Unchecked GetLexerCount() Return Value
34Monitor
CVE-2026-57233Notepad++: Path Traversal (Zip Slip) in WinGup Plugin Extraction
32Monitor
CVE-2026-86054Notepad++: Stack Buffer Overflow in `NppParameters::writeSession` via overlong session path
31Monitor

Published before and after this one in the same product

← EarlierCVE-2026-71858Aug 17, 2026 · Notepad++: shortcuts.xml Macro HMAC Bypass Enables Conditional Elevated Command Execution
21Monitor
← EarlierCVE-2026-85288Sep 22, 2026 · Notepad++: Shortcuts.xml macro HMAC bypass still reachable via the "Run a Macro Multiple Times" dialog
26Monitor
Later →CVE-2026-86056Sep 22, 2026 · Notepad++: Null pointer dereference in NPPM_SAVESESSION message handler causes crash (DoS)
22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
notepad-plus-plus notepad-plus-plus	8.9.8 · description	Vendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

notepad-plus-plus/notepad-plus-pluscommit 9edf40f

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

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Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-26-1158 · Sep 23, 2026(Notepad++ Güvenlik Bildirimi)

All national notices →

Technical details

Attack conditions

Someone with local access to the system can trigger it.
A low-privileged account is enough.
A user must open a link or visit a page.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

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

Weakness class (CWE)

CWE-347 · Improper Verification of Cryptographic Signature

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H

nvd-secondary

Root cause

The verifier takes the algorithm to verify with from the token’s own header. Untrusted data ends up deciding its own verification rule.

The bug in code

The whole CWE-347 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1const claims = jwt.verify(token, publicKey);

Fixed

1const claims = jwt.verify(token, publicKey, {
2  algorithms: ["RS256"],
3  issuer: "https://id.example.com",
4  audience: "portal",
5});

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

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Change log

Fix✗ → ✓Sep 29, 2026, 11:58 AM UTC

For records you follow, these changes also arrive as notifications. →

References

github.com/notepad-plus-plus/notepad-plus-plus/commit/9edf40f725ce62b26c454905e39f0f7fdbbb3ffa

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records