CVE-2026-74766
📛 CVE Title
Net::IDN::Punycode versions from 2.301 before 2.590 for Perl allow a heap use-after-free via a decoded code point that reallocates the output buffer in decode_punycode
Description
Net::IDN::Punycode versions from 2.301 before 2.590 for Perl allow a heap use-after-free via a decoded code point that reallocates the output buffer in decode_punycode. The XS backend inserts each decoded code point into the string buffer of the scalar it returns. decode_punycode computes the insertion pointer first and only then grows the buffer when the code point does not fit. The growth reallocates the buffer and updates every pointer except the insertion pointer, so the move that follows and the write of the code point go through a freed pointer. The buffer starts at twice the label length, and a code point above U+FFFF takes four bytes in the output, so a label of such code points outgrows it and forces the reallocation. Version 2.301, the fix for CVE-2016-15059, introduced the defect. Only the XS backend is affected. Decoding an attacker-supplied punycode label reads and writes freed heap memory.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- CPANSec
- CVSS severity
- —
- CVSS score
- —
- CVSS vector
- —
- Effective score
- 8.4 / 10 HIGH source: NVD
- CWE(s)
-
CWE-416 - Reserved
- 2026-08-15
- Published
- 2026-09-22 07:19 UTC
- Last updated
- 2026-09-22 12:41 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/74xxx/CVE-2026-74766.json
- Linked Threat
- CVE-2026-74766 — Net::IDN::Punycode versions from 2.301 before 2.590 for Perl allow a heap use-after-free via a decoded code point that reallocates the output buffer in decode_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
- 8.4 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
- NVD CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Exploitability subscore
- 2.5 / 10
- Impact subscore
- 5.9 / 10
- EPSS score
- 0.0016 (probability of exploitation in next 30 days)
- EPSS percentile
- 5.21% vs all CVEs — higher = more likely to be exploited, as of 2026-09-22
NVD / KEV / EPSS data refreshed 2026-09-23 02:44 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-2026-84290 - Assigner
- CPANSec
- Published
- Sep 22, 2026, 7:19:09 AM
- Updated
- Sep 22, 2026, 12:41:52 PM
- EUVD base score (CVSS 3.1)
-
8.4 / 10
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EUVD-reported EPSS
- 0.1600
- Aliases
-
GHSA-qffm-j59f-77qw
ENISA description: Net::IDN::Punycode versions from 2.301 before 2.590 for Perl allow a heap use-after-free via a decoded code point that reallocates the output buffer in decode_punycode. The XS backend inserts each decoded code point into the string buffer of the scalar it returns. decode_punycode computes the insertion pointer first and only then grows the buffer when the code point does not fit. The growth reallocates the buffer and updates every pointer except the insertion pointer, so the move that follows and the write of the code point go through a freed pointer. The buffer starts at twice the label length, and a code point above U+FFFF takes four bytes in the output, so a label of such code points outgrows it and forces the reallocation. Version 2.301, the fix for CVE-2016-15059, introduced the defect. Only the XS backend is affected. Decoding an attacker-supplied punycode label reads and writes freed heap memory.
EUVD references (4)
- https://metacpan.org/release/PJCJ/Net-IDN-Encode-2.590-TRIAL/changes
- https://github.com/robrwo/Net-IDN-Encode/commit/259e74c5739175b063c5393a4ce4a0705678ba61.patch
- https://github.com/robrwo/Net-IDN-Encode/commit/2fbc71e4d8517ab65c5d5d35fda086371b735a3f.patch
- https://www.cve.org/CVERecord?id=CVE-2016-15059
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| — | — |
2.301 (affected)
|
— |
Vendor references (4)
References embedded in the original CVE record by the assigning CNA.
- https://metacpan.org/release/PJCJ/Net-IDN-Encode-2.590-TRIAL/changes release-notes
- https://github.com/robrwo/Net-IDN-Encode/commit/259e74c5739175b063c5393a4ce4a0705678ba61.patch patch
- https://github.com/robrwo/Net-IDN-Encode/commit/2fbc71e4d8517ab65c5d5d35fda086371b735a3f.patch patch
- https://www.cve.org/CVERecord?id=CVE-2016-15059 related
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 (4)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://github.com/robrwo/Net-IDN-Encode/commit/259e74c5739175b063c5393a4ce4a0705678ba61.patch 9b29abf9-4ab0-4765-b253-1875cd9b441e
- https://github.com/robrwo/Net-IDN-Encode/commit/2fbc71e4d8517ab65c5d5d35fda086371b735a3f.patch 9b29abf9-4ab0-4765-b253-1875cd9b441e
- https://metacpan.org/release/PJCJ/Net-IDN-Encode-2.590-TRIAL/changes 9b29abf9-4ab0-4765-b253-1875cd9b441e
- https://www.cve.org/CVERecord?id=CVE-2016-15059 9b29abf9-4ab0-4765-b253-1875cd9b441e
Remediations (16)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blogs.oracle.com
For more information about the Critical Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.
2026-09-23 15:44 UTC -
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 15:44 UTC -
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 15:44 UTC -
web:support.apple.com
This document describes the security content of iOS 26.6 and iPadOS 26.6.
2026-09-23 15:44 UTC -
web:support.microsoft.com
This Hotpatch update for Windows 11, version 25H2 and 24H2 (KB5079420), improves functionality, performance, and reliability. To learn more about differences between security updates, optional non-security preview updates, out-of-band (OOB) updates, and continuous innovation, see Windows monthly updates explained. For information on Windows update terminology, see the different types of ...
2026-09-23 15:44 UTC -
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 9th of June 2026 , SAP security patch day saw the release of 15 new security notes.
2026-09-23 15:44 UTC -
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 15:44 UTC -
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 15:44 UTC -
web:www.oracle.com
This Critical Security Patch Update contains 35 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Security Patch Update and other Oracle Software Security Assurance activities is located at May 2026 Critical Security Patch Update: Executive Summary and Analysis.
2026-09-23 15:44 UTC -
web:www.veeam.com
When a vulnerability is identified, our team promptly develops a patch to address and mitigate the risk. In line with our dedication to transparency, we publicly disclose the vulnerability and provide detailed mitigation information.
2026-09-23 15:44 UTC -
web:aicybr.com
Applicability is CVE - and release-specific. Compare each instance's exact family, patch and hot- fix level with ServiceNow's current advisory before a maintenance window. Hosted and self-hosted remediation ServiceNow-hosted instances ServiceNow says it deployed the security update to hosted instances.
2026-09-25 10:07 UTC -
web:catalog.update.microsoft.com
Welcome to the Microsoft Update Catalog site. We want your feedback! Visit our newsgroup or send us an email to provide us with your thoughts and suggestions. To get started using the site, enter in your search terms in the Search box above or visit our FAQ for search tips. |Newsgroup|Send us your feedback
2026-09-25 10:07 UTC -
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.
2026-09-25 10:07 UTC -
web:www.aikido.dev
CVE remediation is fixing known flaws in the software you run. Why upgrading often fails, what remediation actually involves, and how backporting fixes it.
2026-09-25 10:07 UTC -
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 ...
2026-09-25 10:07 UTC -
web:www.whatsapp.com
CVE - 2026 -23863 An attachment spoofing issue in WhatsApp for Windows prior to v2.3000.1032164386.258709 could have allowed maliciously formatted documents with embedded NUL bytes in the filename to be shown in the application as one type of file but run as an executable when opened. We have not seen evidence of exploitation in the wild. Acknowledgements: External Researcher via Meta Bug Bounty ...
2026-09-25 10:07 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-74766.json.
{
"containers": {
"adp": [
{
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 8.4,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
}
},
{
"other": {
"content": {
"id": "CVE-2026-74766",
"options": [
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"Exploitation": "none"
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{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-09-22T12:41:49.066140Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-09-22T12:41:52.010Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"collectionURL": "https://cpan.org/modules",
"defaultStatus": "unaffected",
"modules": [
"Net::IDN::Punycode"
],
"packageName": "Net-IDN-Encode",
"packageURL": "pkg:cpan/Net-IDN-Encode",
"programFiles": [
"lib/Net/IDN/Punycode.xs"
],
"programRoutines": [
{
"name": "Net::IDN::Punycode::decode_punycode"
}
],
"repo": "https://github.com/robrwo/Net-IDN-Encode",
"versions": [
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"value": "Net::IDN::Punycode versions from 2.301 before 2.590 for Perl allow a heap use-after-free via a decoded code point that reallocates the output buffer in decode_punycode.\n\nThe XS backend inserts each decoded code point into the string buffer of the scalar it returns. decode_punycode computes the insertion pointer first and only then grows the buffer when the code point does not fit. The growth reallocates the buffer and updates every pointer except the insertion pointer, so the move that follows and the write of the code point go through a freed pointer. The buffer starts at twice the label length, and a code point above U+FFFF takes four bytes in the output, so a label of such code points outgrows it and forces the reallocation.\n\nVersion 2.301, the fix for CVE-2016-15059, introduced the defect. Only the XS backend is affected.\n\nDecoding an attacker-supplied punycode label reads and writes freed heap memory."
}
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"problemTypes": [
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"description": "CWE-416 Use After Free",
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"orgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
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"references": [
{
"tags": [
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],
"url": "https://metacpan.org/release/PJCJ/Net-IDN-Encode-2.590-TRIAL/changes"
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{
"tags": [
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"url": "https://github.com/robrwo/Net-IDN-Encode/commit/259e74c5739175b063c5393a4ce4a0705678ba61.patch"
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},
{
"tags": [
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"url": "https://www.cve.org/CVERecord?id=CVE-2016-15059"
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"solutions": [
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"lang": "en",
"value": "Upgrade to Net-IDN-Encode 2.590-TRIAL or later."
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],
"source": {
"discovery": "UNKNOWN"
},
"timeline": [
{
"lang": "en",
"time": "2016-12-03T00:00:00.000Z",
"value": "Version 2.301 released, introducing the defect."
},
{
"lang": "en",
"time": "2026-09-17T00:00:00.000Z",
"value": "Version 2.590-TRIAL released with fix."
}
],
"title": "Net::IDN::Punycode versions from 2.301 before 2.590 for Perl allow a heap use-after-free via a decoded code point that reallocates the output buffer in decode_punycode",
"x_generator": {
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"cveId": "CVE-2026-74766",
"datePublished": "2026-09-22T07:19:09.359Z",
"dateReserved": "2026-08-15T21:52:57.406Z",
"dateUpdated": "2026-09-22T12:41:52.010Z",
"state": "PUBLISHED"
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"dataVersion": "5.2"
}