CVE-2026-4177

criticalpriority · track · 0EPSS 0.004 · 39 %ileDEEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.45% (39th) EPSS

CVSS 9.1 · critical

Is it mine?

43 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · cert_bund · suse_csaf

EPSS · scored 2026-10-27

YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter. The heap overflow occurs when class names exceed the initial 512-byte allocation. The base64 decoder could read past the buffer end on trailing newlines. strtok mutated n->type_id in place, corrupting shared node data. A memory leak occurred in syck_hdlr_add_anchor when a node already had an anchor. The incoming anchor string 'a' was leaked on early return.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

Fixedperl-YAML-Syck-0:1.30-6.el8_10.x86_64 as component of SUSE Liberty Linux 8suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedperl-YAML-Syck-0:1.30-6.el8_10.aarch64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-0:1.30-6.el8_10.ppc64le as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-0:1.30-6.el8_10.s390x as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-0:1.30-6.el8_10.src as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-0:1.30-6.el8_10.x86_64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-debuginfo-0:1.30-6.el8_10.aarch64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-debuginfo-0:1.30-6.el8_10.ppc64le as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-debuginfo-0:1.30-6.el8_10.s390x as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-debuginfo-0:1.30-6.el8_10.x86_64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-debugsource-0:1.30-6.el8_10.aarch64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-debugsource-0:1.30-6.el8_10.ppc64le as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-debugsource-0:1.30-6.el8_10.s390x as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-debugsource-0:1.30-6.el8_10.x86_64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:6470
Fixedperl-YAML-Syck-0:1.27-3.el7_9.1.ppc64 as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:8311
Fixedperl-YAML-Syck-0:1.27-3.el7_9.1.ppc64le as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:8311
Fixedperl-YAML-Syck-0:1.27-3.el7_9.1.s390x as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:8311
Fixedperl-YAML-Syck-0:1.27-3.el7_9.1.src as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:8311
Fixedperl-YAML-Syck-0:1.27-3.el7_9.1.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:8311
Fixedperl-YAML-Syck-debuginfo-0:1.27-3.el7_9.1.ppc64 as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:8311
Fixedperl-YAML-Syck-debuginfo-0:1.27-3.el7_9.1.ppc64le as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:8311
Fixedperl-YAML-Syck-debuginfo-0:1.27-3.el7_9.1.s390x as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:8311
Fixedperl-YAML-Syck-debuginfo-0:1.27-3.el7_9.1.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2026:8311
Workaroundperl-YAML-Syck-0:1.30-6.el8_10.aarch64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-0:1.30-6.el8_10.ppc64le as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-0:1.30-6.el8_10.s390x as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-0:1.30-6.el8_10.src as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-0:1.30-6.el8_10.x86_64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debuginfo-0:1.30-6.el8_10.aarch64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debuginfo-0:1.30-6.el8_10.ppc64le as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debuginfo-0:1.30-6.el8_10.s390x as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debuginfo-0:1.30-6.el8_10.x86_64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debugsource-0:1.30-6.el8_10.aarch64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debugsource-0:1.30-6.el8_10.ppc64le as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debugsource-0:1.30-6.el8_10.s390x as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debugsource-0:1.30-6.el8_10.x86_64 as a component of Red Hat Enterprise Linux CRB (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-0:1.27-3.el7_9.1.ppc64 as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-0:1.27-3.el7_9.1.ppc64le as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-0:1.27-3.el7_9.1.s390x as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-0:1.27-3.el7_9.1.src as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-0:1.27-3.el7_9.1.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debuginfo-0:1.27-3.el7_9.1.ppc64 as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debuginfo-0:1.27-3.el7_9.1.ppc64le as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debuginfo-0:1.27-3.el7_9.1.s390x as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundperl-YAML-Syck-debuginfo-0:1.27-3.el7_9.1.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7 ELS)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

cvss

Technical severity, 0–10. One row per scoring source.

9.1

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.3–9.1

v3.19.1criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · ENISA EU

v3.19.1criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondaryexploitability 3.9 · impact 5.2

v3.17.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondaryexploitability 3.9 · impact 3.4

v3.17.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · Red Hat Product Security US

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-120USCWE-120USCWE-122US

affected products (43)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE openSUSEall versionscert_bundDEcpe:/o:suse:opensuse:-
cPanel cPanel/WHM 126.0.63all versionscert_bundDEcpe:/a:cpanel:cpanel_whm:126.0.63
cPanel cPanel/WHM <110.0.93all versionscert_bundDE
cPanel cPanel/WHM <126.0.50all versionscert_bundDE
cPanel cPanel/WHM <134.0.13all versionscert_bundDE
cPanel cPanel/WHM <134.0.30all versionscert_bundDE
cPanel cPanel/WHM <136.0.0all versionscert_bundDE
cPanel cPanel/WHM <136.0.14all versionscert_bundDE
cPanel cPanel/WHM <137.9999.96all versionscert_bundDE
cPanel cPanel/WHM< 110.0.93cert_bundDE
cPanel cPanel/WHM< 126.0.50cert_bundDE
cPanel cPanel/WHM< 134.0.13cert_bundDE
cPanel cPanel/WHM< 134.0.30cert_bundDE
cPanel cPanel/WHM< 136.0.0cert_bundDE
cPanel cPanel/WHM< 136.0.14cert_bundDE
cPanel cPanel/WHM< 137.9999.96cert_bundDE
TODDR YAML::Syck≤ 0 ≤1.36enisa_euvdEU

showing 20 of 43

advisories (4)

Vendor and ecosystem advisories describing this.

RHSA-2026:6470security update for perl-YAML-Syck2026-04-02csaf · suse_csafDE
security update for perl-YAML-Syck
RHSA-2026:6470Red Hat Security Advisory: perl-YAML-Syck security update2026-04-02csaf · redhat_csafUS
An update for perl-YAML-Syck is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
RHSA-2026:8311Red Hat Security Advisory: perl-YAML-Syck security update2026-04-15csaf · redhat_csafUS
An update for perl-YAML-Syck is now available for Red Hat Enterprise Linux 7 Extended Lifecycle Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
WID-SEC-W-2026-0939cPanel cPanel/WHM (perl-YAML-Syck): Schwachstelle ermöglicht Codeausführung und DoSDeutsch2026-03-31csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in cPanel cPanel/WHM ausnutzen, um potenziell beliebigen Code auszuführen oder einen Denial-of-Service-Zustand zu verursachen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund suse_csaf redhat_csaf NVD CVE.org MITRE

published 2026-03-16modified 2026-07-15

references (14)

External citations — patches, advisories, analysis.

scry

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