CVE-2026-4177Disclosure(toddr / yaml\)

LOWCVSS 9.1 · CRITICAL

Signal is active with 1 mentions in latest observed window

Immediate actions

Patch toddr yaml\ systems immediately

Recommended action window: Monitor and triage in normal cycle

NVD description

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.

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0.5/ 10 priority

Sources & remediation

Patch / fix

https://github.com/cpan-authors/YAML-Syck/commit/e8844a31c8cf0052914b198fc784ed4e6b8ae69e.patch

Vendor / third-party advisories

http://www.openwall.com/lists/oss-security/2026/03/16/6

Other references

Weakness type (CWE)

CWE-122CWE-120

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

AVAILABLE

Momentum

STABLE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

yaml\

Threat summary

Patch or workaround signal is available
5 mentions across 2 observed days
Momentum state: stable

What's happening

Patch or workaround mentioned in 1 signal
Technical details provided in 5 signals
Disclosure: 4 classified signals
General: 1 classified signal
Peaked 1d ago at 4 mentions (2026-03-17); latest day: 1
5 total mentions across 2 days

Affected systems

Vendors

toddr

Products

yaml\

1 version affected across 1 product

Deep dive

Activity timeline5 mentions / 2d

Signal classification2 categories

Disclosure

480.0%

General

120.0%

Referenced assets5 URLs

By indicator

Classification over time

Date	Total	Labels

2026-03-17	4	Disclosure3General1
2026-03-31	1	Disclosure1

Full discourse5 posts

Open Source Security mailing list@oss_security205d
Disclosure
Perl CPAN CVE-2026-4177: YAML::Syck versions through 1.36 has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter https://www.openwall.com/lists/oss-security/2026/03/16/6
Post summary
A mailing‑list post discloses CVE-2026-4177, highlighting a high‑severity heap buffer overflow in YAML::Syck, but offers no evidence of active exploitation, patch availability, or PoC details.
00031442
4.4K followersView on X
The Hacker Wire@TheHackerWire205d
Disclosure
🔴 CVE-2026-4177 - Critical 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 ... https://www.thehackerwire.com/vulnerability/CVE-2026-4177/ https://t.co/T06LjmTvWE
Post summary
The tweet announces CVE‑2026‑4177, a critical heap buffer overflow in YAML::Syck for Perl, provides a link to a vulnerability report, but contains no PoC, exploit code, patch, or evidence of active exploitation.
0001079
138 followersView on X
ThreatCluster@threatcluster191d
Disclosure
BREAKING: Fedora 42 and 43 hit by CVE-2026-4177 in perl-YAML-Syck, heap buffer overflow and memory leak flaws fixed in version 1.39+. https://threatcluster.io/cluster/fedora-42-and-43-perl-yaml-syck-buffer-overflow-vulnerabilit-dcc44364
Post summary
The post announces a heap buffer overflow vulnerability (CVE‑2026‑4177) affecting Fedora 42/43, provides technical details, and notes that it has been fixed in version 1.39+.
0000049
128 followersView on X
CVE@CVEnew205d
Disclosure
CVE-2026-4177 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 o… https://www.cve.org/CVERecord?id=CVE-2026-4177
Post summary
CVE-2026-4177 identifies a high‑severity heap buffer overflow in YAML::Syck through version 1.36, but no PoC, exploit, or patch information is provided.
0000098
56.7K followersView on X
CyberDudeBivash® | Global Cybersecurity Company@cyberbivash206d
General
🚨 CYBERDUDEBIVASH SENTINEL APEX ALERT 🚨 Threat: CVE-2026-4177 - YAML::Syck versions through 1.36 for Perl has several potential security vulnerabilities including a high-severity heap buffer overflow in the YAML emitter Intel Report: https://ift.tt/ukxNKv9
Post summary
A threat alert highlights CVE‑2026‑4177 as a high‑severity heap buffer overflow in YAML::Syck for Perl, with no evidence yet of exploitation or patches.
0000048
336 followersView on X

CPE platform detail1 entries

Part:

Vendor:

Product:

Version:

Target SW:

Target HW:

1 of 1 entries

Part	Vendor	Product	Version	Target SW	Target HW
App	toddr	yaml\	\	-	-

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Back to dashboard toddr CVEs yaml\ vulnerabilities

What researchers are saying

CVE-2026-4177

ThreatCluster[verified]@threatclusterDisclosure

The post announces a heap buffer overflow vulnerability (CVE‑2026‑4177) affecting Fedora 42/43, provides technical details, and notes that it has been fixed in version 1.39+.

Open Source Security mailing list@oss_securityDisclosure

A mailing‑list post discloses CVE-2026-4177, highlighting a high‑severity heap buffer overflow in YAML::Syck, but offers no evidence of active exploitation, patch availability, or PoC details.

The Hacker Wire@TheHackerWireDisclosure

The tweet announces CVE‑2026‑4177, a critical heap buffer overflow in YAML::Syck for Perl, provides a link to a vulnerability report, but contains no PoC, exploit code, patch, or evidence of active exploitation.

CVE@CVEnewDisclosure

CVE-2026-4177 identifies a high‑severity heap buffer overflow in YAML::Syck through version 1.36, but no PoC, exploit, or patch information is provided.

CyberDudeBivash® | Global Cybersecurity Company@cyberbivashGeneral

A threat alert highlights CVE‑2026‑4177 as a high‑severity heap buffer overflow in YAML::Syck for Perl, with no evidence yet of exploitation or patches.