# CVE-2026-4177: perl-YAML-Syck: This module provides a Perl interface to the libsyck data serialization library

CVE-2026-4177 is fixed in 5 products on 1 platform, first by DEBIAN-CVE-2026-4177, released March 16, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-4177
- Priority: High
- CVSS: 9.1 (Important)
- EPSS: 0.0046
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 16, 2026

## Description

This module provides a Perl interface to the libsyck data serialization library. It exports the Dump and Load functions for converting Perl data structures to YAML strings, and the other way around.  Security Fix(es):  * perl-YAML-Syck: YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter (CVE-2026-4177)  For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libyaml-syck-perl Debian 12.15 (bookworm) | 1.34-2+deb12u2 | [DSA-6175-1](https://patchblox.com/security/data/fix/linux/dsa-6175-1.md) | Mar 22, 2026 |
| Linux | libyaml-syck-perl Debian 13.5 (trixie) | 1.34-2+deb13u2 | [DSA-6175-1](https://patchblox.com/security/data/fix/linux/dsa-6175-1.md) | Mar 22, 2026 |
| Linux | libyaml-syck-perl Debian 14 | 1.36-2 | [DEBIAN-CVE-2026-4177](https://patchblox.com/security/data/fix/linux/debian-cve-2026-4177.md) | Mar 16, 2026 |
| Linux | perl-YAML-Syck RHEL 8 | 0:1.30-6.el8_10 | [RHSA-2026:6470](https://patchblox.com/security/data/fix/linux/rhsa-2026-6470.md) | Apr 15, 2026 |
| Linux | perl-YAML-Syck almalinux 8 | 1.30-6.el8_10 | [ALSA-2026:6470](https://patchblox.com/security/data/fix/linux/alsa-2026-6470.md) | Apr 2, 2026 |
| Linux | perl-YAML-Syck amzn 2023 | 1.37-1.amzn2023.0.1 | [ALAS2023-2026-1517](https://patchblox.com/security/data/fix/linux/alas2023-2026-1517.md) | Mar 30, 2026 |
| Linux | perl-YAML-Syck ol 8 | 0:1.30-6.el8_10 | [ELSA-2026-6470](https://patchblox.com/security/data/fix/linux/elsa-2026-6470.md) | Apr 3, 2026 |
| Linux | perl-YAML-Syck rocky 8 | 0:1.30-6.el8_10 | [RLSA-2026:6470](https://patchblox.com/security/data/fix/linux/rlsa-2026-6470.md) | Apr 9, 2026 |
| Linux | perl-YAML-Syck-debuginfo amzn 2023 | 1.37-1.amzn2023.0.1 | [ALAS2023-2026-1517](https://patchblox.com/security/data/fix/linux/alas2023-2026-1517.md) | Mar 30, 2026 |
| Linux | perl-YAML-Syck-debugsource amzn 2023 | 1.37-1.amzn2023.0.1 | [ALAS2023-2026-1517](https://patchblox.com/security/data/fix/linux/alas2023-2026-1517.md) | Mar 30, 2026 |
| Linux | perl-YAML-Syck-tests amzn 2023 | 1.37-1.amzn2023.0.1 | [ALAS2023-2026-1517](https://patchblox.com/security/data/fix/linux/alas2023-2026-1517.md) | Mar 30, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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