CVE-2026-87082

CVEs › CVE-2026-87082

Description

Net::IDN::Punycode versions before 2.590 for Perl hang, crash or return a wrong label via unvalidated malformed UTF-8 in encode_punycode. Neither backend checks that its input is well-formed UTF-8, so a string with the UTF-8 flag set over malformed bytes, as the :utf8 PerlIO layer produces from any malformed input, reaches the encoder unchecked. On perl 5.32 and later the XS backend reports a malformed sequence with a length of `(STRLEN)-1`, so the scan steps back one byte instead of forward and never ends. On earlier perls the XS returns a valid label for a different name. The pure-Perl backend runs a regex over the flagged string. Depending on the bytes, it aborts with SIGBUS on perl 5.28 and later, dies with a panic, or returns a wrong label. The documented conversion functions match the label against Unicode properties first and that match dies on such a string, so only a direct call to encode_punycode reaches the defect. The decoder is not affected. A direct caller encoding attacker-supplied bytes hangs, crashes or gets a label for a name the input never held.

Overview

State: PUBLISHED
Assigner (CNA): CPANSec
CVSS severity: —
CVSS score: —
CVSS vector: —
Effective score: 7.5 / 10 HIGH source: NVD
CWE(s): CWE-835, CWE-1286
Reserved: 2026-09-08
Published: 2026-09-22 07:25 UTC
Last updated: 2026-09-22 17:07 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/87xxx/CVE-2026-87082.json
Linked Threat: CVE-2026-87082 — Net::IDN::Punycode versions before 2.590 for Perl hang, crash or return a wrong label via unvalidated malformed UTF-8 in encode_punycode

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-09-22 08:16:40 UTC
NVD last modified: 2026-09-22 19:07:00 UTC
NVD CVSS v3.1: 7.5 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Exploitability subscore: 3.9 / 10
Impact subscore: 3.6 / 10
EPSS score: 0.0016 (probability of exploitation in next 30 days)
EPSS percentile: 5.62% vs all CVEs — higher = more likely to be exploited, as of 2026-09-22

NVD / KEV / EPSS data refreshed 2026-09-23 02:35 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-84295
Assigner: CPANSec
Published: Sep 22, 2026, 7:25:37 AM
Updated: Sep 22, 2026, 5:07:32 PM
EUVD base score (CVSS 3.1): 7.5 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EUVD-reported EPSS: 0.1600
Aliases: GHSA-4v8j-337r-265v

ENISA description: Net::IDN::Punycode versions before 2.590 for Perl hang, crash or return a wrong label via unvalidated malformed UTF-8 in encode_punycode. Neither backend checks that its input is well-formed UTF-8, so a string with the UTF-8 flag set over malformed bytes, as the :utf8 PerlIO layer produces from any malformed input, reaches the encoder unchecked. On perl 5.32 and later the XS backend reports a malformed sequence with a length of `(STRLEN)-1`, so the scan steps back one byte instead of forward and never ends. On earlier perls the XS returns a valid label for a different name. The pure-Perl backend runs a regex over the flagged string. Depending on the bytes, it aborts with SIGBUS on perl 5.28 and later, dies with a panic, or returns a wrong label. The documented conversion functions match the label against Unicode properties first and that match dies on such a string, so only a direct call to encode_punycode reaches the defect. The decoder is not affected. A direct caller encoding attacker-supplied bytes hangs, crashes or gets a label for a name the input never held.

EUVD references (5)

Affected products (1)

Vendor	Product	Versions	Platforms
—	—	`0` (affected)	—

Vendor references (5)

References embedded in the original CVE record by the assigning CNA.

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

NVD-tagged references (6)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

http://www.openwall.com/lists/oss-security/2026/09/22/17 af854a3a-2127-422b-91ae-364da2661108
https://github.com/robrwo/Net-IDN-Encode/commit/0918fb4a951ed5f4494c4cf202419c2842507ea4.patch 9b29abf9-4ab0-4765-b253-1875cd9b441e
https://github.com/robrwo/Net-IDN-Encode/commit/572af0183b3a6294e22c6b509268da09697cf77d.patch 9b29abf9-4ab0-4765-b253-1875cd9b441e
https://github.com/robrwo/Net-IDN-Encode/commit/59dc7f2c605a897bcbfe0ac5eb2b8dbe6792348d.patch 9b29abf9-4ab0-4765-b253-1875cd9b441e
https://github.com/robrwo/Net-IDN-Encode/commit/accb6df57ad107ec0c4bfb27b21551eed97c700e.patch 9b29abf9-4ab0-4765-b253-1875cd9b441e
https://metacpan.org/release/PJCJ/Net-IDN-Encode-2.590-TRIAL/changes 9b29abf9-4ab0-4765-b253-1875cd9b441e

Remediations (18)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

Security Advisory - Action Required - Active Exploitation of CVE-2026 ...

web:blog.checkpoint.com

CVE - 2026 -93616 is a newly discovered zero-day vulnerability in Security Management, and a fix is available now as part of this advisory. Fixes are available for both vulnerabilities. Customers running affected versions should install the applicable fixes immediately. Affected versions and remediation instructions are detailed below.

2026-09-23 15:42 UTC
August 2026 cumulative update - .NET Framework | Microsoft Learn

web:learn.microsoft.com

Unlike traditional cumulative updates that patch individual components, this update delivers the full .NET Framework 3.5 product as a standalone installer. It replaces any previously installed version.

2026-09-23 15:42 UTC
Security Update Guide - Microsoft Security Response Center

web:msrc.microsoft.com

Security Update Guide - Microsoft Security Response Center

2026-09-23 15:42 UTC
Cisco Advance Notification for Publication of September 16, 2026 ...

web:sec.cloudapps.cisco.com

On September 16, 2026 , the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate these vulnerabilities, Cisco strongly recommends that customers upgrade to the fixed software that is indicated in the advisories. For more information about changes in Cisco PSIRT vulnerability disclosure, see Strengthening the ...

2026-09-23 15:42 UTC
Microsoft Patch Tracker (September 2026): Exploit-Ranked | Senserva

web:senserva.com

Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.

2026-09-23 15:42 UTC
Description of the security update for Office 2016: August 11, 2026 ...

web:support.microsoft.com

Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2016. It doesn't apply to the Office 2016 Click-to-Run editions, such as Microsoft Office 365 Home. (See What version of Office am I using?) How to get and install the update Method 1: Microsoft Update This update is available from Microsoft Update. When you turn on ...

2026-09-23 15:42 UTC
SAP Security Patch Day - May 2026

web:support.sap.com

SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 12 th of May 2026 , SAP security patch day saw the release of 15 new security notes.

2026-09-23 15:42 UTC
August 2026 CVE Advisory Notification - Security

web:support.servicenow.com

Due to additional analysis provided by the security researcher who discovered CVE - 2026 -6876, we have upgraded the severity rating of CVE - 2026 -6876 from High to Critical. This change affects only the severity

2026-09-23 15:42 UTC
Oracle Critical Patch Update Advisory - July 2026

web:www.oracle.com

This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.

2026-09-23 15:42 UTC
Oracle Critical Security Patch Update Advisory - June 2026

web:www.oracle.com

Additional CVEs addressed are: The patch for CVE - 2026 -34481 also addresses CVE - 2026 -34477, CVE - 2026 -34478, CVE - 2026 -34479, and CVE - 2026 -34480. Oracle Fusion Middleware Risk Matrix This Critical Security Patch Update contains 106 new security patches for Oracle Fusion Middleware. 53 of these vulnerabilities may be remotely exploitable without authentication, i.e., may be exploited over a ...

2026-09-23 15:42 UTC
CVE-2026-87582 · Google · CVSS 8.3 · CVE Brief Analyst Report

web:cvebrief.com

Google · Chrome A confused deputy vulnerability exists in the DataTransfer component of Google Chrome, allowing a remote attacker to achieve sandbox escape and arbitrary code execution via a crafted HTML page. Quick facts CVSS score 8.3 (High) Fix available Yes: 153..8010.36 ( CVE record) Affected versions Versions prior to 153..8010.36 First covered September 12, 2026 daily brief Last ...

2026-09-25 10:07 UTC
CVE-2026-87902: Attackers Started Probing WordPress Sites Hours After ...

web:patchstack.com

Yesterday we wrote up CVE - 2026 -87902, the unauthenticated local file inclusion in WordPress page template resolution fixed in 7.1.2. That post covered the sink,

2026-09-25 10:07 UTC
Google fixes the seventh actively exploited Chrome zero-day of 2026

web:securityaffairs.com

Google patched 230 Chrome flaws, including an actively exploited V8 bug that could let attackers run arbitrary code through a crafted HTML page. Google released a Chrome update fixing 230 security vulnerabilities, including one already exploited in the wild tracked as CVE - 2026 -87491 (CVSS score of 8 ...

2026-09-25 10:07 UTC
CVE-2026-87902 in WordPress Enables Conditional RCE

web:socradar.io

For CVE - 2026 -87902, this visibility can help teams move from tracking the vulnerability to identifying potentially exposed WordPress assets and prioritizing remediation as the threat landscape changes.

2026-09-25 10:07 UTC
CVE-2026-85046 Explained: Inside Chrome's V8 Zero-Day | The CyberSec Guru

web:thecybersecguru.com

CVE - 2026 -85046 is a V8 type confusion zero-day already exploited in Chrome. Here's how the read/write primitive works, and how to patch immediately

2026-09-25 10:07 UTC
PaperCut NG/MF Zero-day Vulnerability Exploited in the Attacks (CVE ...

web:threatprotect.qualys.com

PaperCut released an Urgent Security Advisory to address two actively exploited vulnerabilities, tracked as CVE - 2026 -82078 & CVE - 2026 -81578, impacting all versions of PaperCut NG and PaperCut MF.

2026-09-25 10:07 UTC
CISA KEV September 16, 2026: Three CVE Patch Analysis

web:www.secpod.com

Patch Timeline & Exploitation Gap Analysis The September 16, 2026 dataset contains three CISA KEV vulnerabilities. Each record was added to the catalog on September 16, 2026 and assigned a remediation deadline of September 19, 2026 . Consequently, all three vulnerabilities have an identical three-calendar-day KEV inclusion-to- remediation window.

2026-09-25 10:07 UTC
CVE-2026-85046 | Google Chromium V8 Vulnerability | UpGuard

web:www.upguard.com

CVE - 2026 -85046 is a high-severity (8.8) type confusion vulnerability in Google Chrome's V8 engine being actively exploited for remote code execution.

2026-09-25 10:07 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-87082.json.

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