CVE-2026-5089
📛 CVE Title
YAML::Syck versions before 1.38 for Perl has an out-of-bounds read
Description
YAML::Syck versions before 1.38 for Perl has an out-of-bounds read. The base60 (sexagesimal) parsing code in perl_syck.h has a buffer underflow bug in both int#base60 and float#base60 handlers. When processing the leftmost segment of a colon-separated value (e.g., the 1 in 1:30:45), the inner while loop can decrement a pointer past the start of the string buffer: while ( colon >= ptr && *colon != ':' ) { colon--; } if ( *colon == ':' ) *colon = '\0'; // colon may be ptr-1 here When no colon is found (final/leftmost segment), colon becomes ptr-1, and the subsequent *colon dereference reads one byte before the allocated buffer.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- CPANSec
- CVSS severity
- high
- CVSS score
- 7.3 / 10
- CVSS vector
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L- Effective score
- 7.3 / 10 HIGH source: CNA overview
- CWE(s)
-
CWE-124 - Reserved
- 2026-03-28
- Published
- 2026-05-12 18:14 UTC
- Last updated
- 2026-05-14 15:51 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/5xxx/CVE-2026-5089.json
- Linked Threat
- CVE-2026-5089 — CVE-2026-5089
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
- 2026-05-12 17:16:21 UTC
- NVD last modified
- 2026-05-14 15:16:49 UTC
- NVD CVSS v3.1
- 7.3 / 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:L/I:L/A:L- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 3.4 / 10
- EPSS score
- 0.0005 (probability of exploitation in next 30 days)
- EPSS percentile
- 14.47% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 07:52 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-2026-29543 - Assigner
- CPANSec
- Published
- May 12, 2026, 4:14:21 PM
- Updated
- May 14, 2026, 1:51:01 PM
- EUVD base score (CVSS 3.1)
-
7.3 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - EUVD-reported EPSS
- 0.0500
- Vendors
- TODDR
- Products
-
YAML::Syck (0 <1.38)
ENISA description: YAML::Syck versions before 1.38 for Perl has an out-of-bounds read. The base60 (sexagesimal) parsing code in perl_syck.h has a buffer underflow bug in both int#base60 and float#base60 handlers. When processing the leftmost segment of a colon-separated value (e.g., the 1 in 1:30:45), the inner while loop can decrement a pointer past the start of the string buffer: while ( colon >= ptr && *colon != ':' ) { colon--; } if ( *colon == ':' ) *colon = '\0'; // colon may be ptr-1 here When no colon is found (final/leftmost segment), colon becomes ptr-1, and the subsequent *colon dereference reads one byte before the allocated buffer.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| TODDR | YAML::Syck |
0 (affected)
|
— |
Vendor references (4)
References embedded in the original CVE record by the assigning CNA.
- https://metacpan.org/release/TODDR/YAML-Syck-1.38/changes release-notes
- https://github.com/cpan-authors/YAML-Syck/issues/132 issue-tracking
- https://github.com/cpan-authors/YAML-Syck/pull/133 issue-tracking
- https://github.com/cpan-authors/YAML-Syck/commit/208a4d3bd1b5cdb4a791a6e3905bd6bd45e9d005.patch patch
MITRE references (4) cveawg.mitre.org
Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.
- https://github.com/cpan-authors/YAML-Syck/commit/208a4d3bd1b5cdb4a791a6e3905bd6bd45e9d005.patch patch
- https://github.com/cpan-authors/YAML-Syck/issues/132 issue-tracking
- https://github.com/cpan-authors/YAML-Syck/pull/133 issue-tracking
- https://metacpan.org/release/TODDR/YAML-Syck-1.38/changes release-notes
Web references (4)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- http://www.openwall.com/lists/oss-security/2026/05/12/16 tenable:www.openwall.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-5089 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-5089 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
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/2026/05/12/16 af854a3a-2127-422b-91ae-364da2661108
- https://github.com/cpan-authors/YAML-Syck/commit/208a4d3bd1b5cdb4a791a6e3905bd6bd45e9d005.patch 9b29abf9-4ab0-4765-b253-1875cd9b441e
- https://github.com/cpan-authors/YAML-Syck/issues/132 9b29abf9-4ab0-4765-b253-1875cd9b441e
- https://github.com/cpan-authors/YAML-Syck/issues/132 134c704f-9b21-4f2e-91b3-4a467353bcc0
- https://github.com/cpan-authors/YAML-Syck/pull/133 9b29abf9-4ab0-4765-b253-1875cd9b441e
- https://metacpan.org/release/TODDR/YAML-Syck-1.38/changes 9b29abf9-4ab0-4765-b253-1875cd9b441e
Remediations (18)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:app.opencve.io
Remediation No vendor fix or workaround currently provided. OpenCVE Recommended Actions Apply the Microsoft security update for CVE - 2026 -41089 from the Microsoft Security Response Center, following the instructions in the update guide.
2026-05-23 20:58 UTC -
web:carthageelectronics.com
Status: Actively exploited — CISA KEV listed — patch by May 12, 2026 What Happened On April 28, 2026 , CISA added CVE - 2026 -32202 to its Known Exploited Vulnerabilities (KEV) catalog with a federal remediation deadline of May 12, 2026 . This vulnerability is the result of an incomplete patch Microsoft released in February for CVE - 2026 -21510.
2026-05-23 20:58 UTC -
web:krebsonsecurity.com
Microsoft expects that exploitation is more likely. May's Patch Tuesday is a welcome respite from April, which saw Microsoft fix a near-record 167 security flaws.
2026-05-23 20:58 UTC -
web:techcommunity.microsoft.com
We wanted to tell you how to address the Exchange Server May 2026 vulnerability CVE - 2026 -42897.
2026-05-23 20:58 UTC -
web:vulert.com
Microsoft's May 2026 Patch Tuesday fixes 138 vulnerabilities, including critical Windows DNS and Netlogon RCE flaws. Learn the risks, key CVEs , mitigation steps, and how Vulert can help.
2026-05-23 20:58 UTC -
web:windowsreport.com
Microsoft has released its May 2026 Patch Tuesday updates for Windows 11 and Windows 10, shipping as KB5089549 and KB5087544. The updates include fixes for more than 130 security vulnerabilities across Windows, Office, SharePoint, DNS components, and core system services, as Bleeping Computer writes. While no publicly disclosed zero-day vulnerabilities were reported this month, the […]
2026-05-23 20:58 UTC -
web:www.bleepingcomputer.com
Today is Microsoft's May 2026 Patch Tuesday, with security updates for 120 flaws and no zero-days disclosed this month.
2026-05-23 20:58 UTC -
web:www.helpnetsecurity.com
Microsoft has marked May 2026 Patch Tuesday by releasing fixes for 120+ CVE -numbered vulnerabilities, none of which are actively exploited.
2026-05-23 20:58 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-05-23 20:58 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-05-23 20:58 UTC -
web:attack.mitre.org
This mitigation can be implemented through the following measures: Regular Operating System Updates Implementation: Apply the latest Windows security updates monthly using WSUS (Windows Server Update Services) or a similar patch management solution. Configure systems to check for updates automatically and schedule reboots during maintenance ...
2026-05-26 02:51 UTC -
web:blog.qualys.com
With Qualys Policy Audit's out-of-the-box mitigation or Compensatory Controls, which reduce the risk of a vulnerability being exploited because the remediation ( fix / patch ) cannot be done immediately, these security controls are not recommended by any industry standards, such as CIS and DISA-STIG.
2026-05-26 02:51 UTC -
web:blog.talosintelligence.com
Microsoft Patch Tuesday for October 2025 — Snort rules and prominent vulnerabilities Microsoft has released its monthly security update for October 2025, addressing 175 Microsoft CVEs and 21 non-Microsoft CVEs . Among these, 17 vulnerabilities are considered critical and 11 are flagged as important and considered more likely to be exploited.
2026-05-26 02:51 UTC -
web:community.ui.com
Published: May 21, 2026 Updated: May 22, 2026 Version: 1.1 Revision: 1.1 Summary 1 of 5 A malicious actor with access to the network and high privileges could exploit an Improper Input Validation vulnerability found in UniFi OS devices to execute a Command Injection. Affected Products: UniFi OS Server (Version 5.0.6 and earlier) Mitigation : Update your UniFi OS Server to Version 5.0.8 or later ...
2026-05-26 02:51 UTC -
web:cyberpress.org
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .
2026-05-26 02:51 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-05-26 02:51 UTC -
web:www.computerworld.com
Here's a look at the most recent Patch Tuesday release from Microsoft as well as a collection of recent updates so you can track what's changed.
2026-05-26 02:51 UTC -
web:www.ninjaone.com
Catalog of Microsoft KB updates with insights on performance & user sentiment. Find out what's working, what's not, & make informed decisions.
2026-05-26 02:51 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-5089.json.
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