CVE-2026-120455

rapidyaml through 0.16.0 Out-of-Bounds Write via ParseEngine::_add_annotation()

CVSS score

6.9

EPSS probability

—

Risk score

0.7

Published

3 h ago

Overview Public Exploits (0)Newsroom Vulnerability Timeline

Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

Impact on My Inventory

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Vulnerability description

DayBreach AI Explanation

Verified against sources

rapidyaml ParseEngine::_add_annotation() Out-of-Bounds Write Vulnerability

Sources read

Source agreement

Tam uyum

Evidence confidence

%55

Short explanation

biojppm rapidyaml through 0.16.0 contains an out-of-bounds write vulnerability in ParseEngine::_add_annotation(). The flaw can lead to stack memory corruption and process crashes.

Why does it matter?

Attackers can supply YAML data with excess anchors or tags to compromise memory integrity and cause process termination.

What should be done?

Follow vendor advisories
Apply available updates
Validate YAML inputs

Chain of evidence and sources2 verified claims

rapidyaml 0.16.0 ve önceki sürümler ParseEngine::_add_annotation() içinde sınır dışı yazma zafiyeti içermektedir.

S0 · daybreach-canonical S1 · cvelist

Zararlı YAML girdileri yığın belleğini bozarak sürecin çökmesine neden olabilir.

S0 · daybreach-canonical S1 · cvelist

Show the technical text from the sources

rapidyaml through 0.16.0 contains an out-of-bounds write vulnerability in ParseEngine::_add_annotation() that allows attackers to corrupt memory by supplying YAML with excess anchors or tags. Attackers can submit YAML with consecutive anchors or tags to overflow the fixed two-element annotation array in release builds, corrupting stack memory and crashing the process.

CVSS vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

CWE: CWE-787

This explanation was compiled automatically from the source records. Scores, active exploitation, patch and exploit status come straight from the sources.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-120455 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

ID	VENDOR	PRODUCT	ACTION
1	biojppm	rapidyaml	View

Total affected vendors: 1|Products: 1

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCORE	VERSION	SEVERITY	VECTOR	SOURCE
6.9	CVSS V40	MEDIUM	CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X	NVD
6.9	CVSS V4_0	MEDIUM	CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N	CVE CNA
6.1	CVSS V31	MEDIUM	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H	NVD
6.1	CVSS V3_1	MEDIUM	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H	CVE CNA

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.

Restrict access to internet-facing services and apply network segmentation.

Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.

Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-120455 is associated with the following CWEs:

CWE-787: Out-of-bounds Write

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-120455 weaknesses.

CAPEC-66: SQL Injection CAPEC-126: Path Traversal CAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureYerel erişim

PermissionsGerekmiyor

User—

Official Sources and Advisories

https://github.com/biojppm/rapidyaml/issues/680vendor-advisory https://github.com/biojppm/rapidyaml/blob/v0.16.0/src/c4/yml/parse_engine.def.hpp#L4307-L4351vendor-advisory https://github.com/biojppm/rapidyaml/blob/v0.16.0/src/c4/yml/parse_engine.def.hpp#L5524-L5535vendor-advisory https://github.com/biojppm/rapidyaml/blob/v0.16.0/src/c4/yml/parse_engine.hpp#L249-L260vendor-advisory rapidyaml v0.16.0 Release Notesvendor-advisory https://hackmd.io/@haindpwn/rapidyaml-parser-annotation-oob-writevendor-advisory VulnCheck Advisory: rapidyaml through 0.16.0 Out-of-Bounds Write via ParseEngine::_add_annotation()vendor-advisory

CVSS Vector Radar Chart

6.9 / 10

Vulnerability Scoring Details

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

Attack VectorLocal

Attack ComplexityLow

Privileges RequiredNone required

User InteractionP

Confidentiality (Gizlilik)Low

Integrity (Bütünlük)P

Availability (Erişilebilirlik)High

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Follow the vendor

biojppm

Weakness Type (CWE & CAPEC)

CWE-787

Get this vulnerability through the API

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