CVE-2026-3407

YosysHQ yosys BLIF File rtlil.h set heap-based overflow

Published Mar 2, 2026 CVSS 4.0 · 4.8 Medium EPSS < 1% KEV · Not listed

Description

A vulnerability was determined in YosysHQ yosys up to 0.62. This affects the function Yosys::RTLIL::Const::set of the file kernel/rtlil.h of the component BLIF File Parser. This manipulation causes heap-based buffer overflow. It is possible to launch the attack on the local host. The exploit has been publicly disclosed and may be utilized. Applying a patch is the recommended action to fix this issue. It appears that the issue is not reproducible all the time.

Analysis

Technical impact

The vulnerability originates in the RTLIL::Const::set function within the BLIF File Parser component, where improperly bounded writes to a heap-allocated buffer can cause a heap-based overflow. This overflow occurs when an attacker supplies a malicious BLIF file that the parser processes. According to the official description, it is possible for local users to trigger the overflow, which may lead to a crash or corruption of program memory. The CVE details do not explicitly claim arbitrary code execution, so any such claim is beyond the stated evidence.

Affected Systems

YosysHQ yosys users running version 0.62 or earlier are affected. The issue is confined to the kernel/rtlil.h component responsible for parsing BLIF files. No newer releases or alternative branches have been reported to contain the flaw. Systems that load untrusted BLIF files locally are susceptible.

Risk and Exploitability

The CVSS score of 4.8 indicates moderate severity, while the EPSS score below 1% suggests a low likelihood of widespread exploitation. The vulnerability is not listed in the CISA KEV catalog. Because the attack vector is local, only users with local filesystem access or attackers who gain local foothold can exploit it. Nonetheless, since heap overflows can degrade reliability or provide a foothold for more advanced attacks, administrators should treat the patch as a priority.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

YosysHQ

yosys

affected

Version	Status	Constraints
`0.1`	affected	—
`0.2`	affected	—
`0.3`	affected	—
`0.4`	affected	—
`0.5`	affected	—
`0.6`	affected	—
`0.7`	affected	—
`0.8`	affected	—
`0.9`	affected	—
`0.10`	affected	—
`0.11`	affected	—
`0.12`	affected	—
`0.13`	affected	—
`0.14`	affected	—
`0.15`	affected	—
`0.16`	affected	—
`0.17`	affected	—
`0.18`	affected	—
`0.19`	affected	—
`0.20`	affected	—
`0.21`	affected	—
`0.22`	affected	—
`0.23`	affected	—
`0.24`	affected	—
`0.25`	affected	—
`0.26`	affected	—
`0.27`	affected	—
`0.28`	affected	—
`0.29`	affected	—
`0.30`	affected	—
`0.31`	affected	—
`0.32`	affected	—
`0.33`	affected	—
`0.34`	affected	—
`0.35`	affected	—
`0.36`	affected	—
`0.37`	affected	—
`0.38`	affected	—
`0.39`	affected	—
`0.40`	affected	—
`0.41`	affected	—
`0.42`	affected	—
`0.43`	affected	—
`0.44`	affected	—
`0.45`	affected	—
`0.46`	affected	—
`0.47`	affected	—
`0.48`	affected	—
`0.49`	affected	—
`0.50`	affected	—
`0.51`	affected	—
`0.52`	affected	—
`0.53`	affected	—
`0.54`	affected	—
`0.55`	affected	—
`0.56`	affected	—
`0.57`	affected	—
`0.58`	affected	—
`0.59`	affected	—
`0.60`	affected	—
`0.61`	affected	—
`0.62`	affected	—

No data.

Vendor Product Versions

Yosyshq

Yosys

Version	Status	Scheme	Platform
`0.1`	affected	generic	—
`0.2`	affected	generic	—
`0.3`	affected	generic	—
`0.4`	affected	generic	—
`0.5`	affected	generic	—
`0.6`	affected	generic	—
`0.7`	affected	generic	—
`0.8`	affected	generic	—
`0.9`	affected	generic	—
`0.10`	affected	generic	—
`0.11`	affected	generic	—
`0.12`	affected	generic	—
`0.13`	affected	generic	—
`0.14`	affected	generic	—
`0.15`	affected	generic	—
`0.16`	affected	generic	—
`0.17`	affected	generic	—
`0.18`	affected	generic	—
`0.19`	affected	generic	—
`0.20`	affected	generic	—
`0.21`	affected	generic	—
`0.22`	affected	generic	—
`0.23`	affected	generic	—
`0.24`	affected	generic	—
`0.25`	affected	generic	—
`0.26`	affected	generic	—
`0.27`	affected	generic	—
`0.28`	affected	generic	—
`0.29`	affected	generic	—
`0.30`	affected	generic	—
`0.31`	affected	generic	—
`0.32`	affected	generic	—
`0.33`	affected	generic	—
`0.34`	affected	generic	—
`0.35`	affected	generic	—
`0.36`	affected	generic	—
`0.37`	affected	generic	—
`0.38`	affected	generic	—
`0.39`	affected	generic	—
`0.40`	affected	generic	—
`0.41`	affected	generic	—
`0.42`	affected	generic	—
`0.43`	affected	generic	—
`0.44`	affected	generic	—
`0.45`	affected	generic	—
`0.46`	affected	generic	—
`0.47`	affected	generic	—
`0.48`	affected	generic	—
`0.49`	affected	generic	—
`0.50`	affected	generic	—
`0.51`	affected	generic	—
`0.52`	affected	generic	—
`0.53`	affected	generic	—
`0.54`	affected	generic	—
`0.55`	affected	generic	—
`0.56`	affected	generic	—
`0.57`	affected	generic	—
`0.58`	affected	generic	—
`0.59`	affected	generic	—
`0.60`	affected	generic	—
`0.61`	affected	generic	—
`0.62`	affected	generic	—

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Upgrade Yosys to the patched version released after the fix (e.g., version 0.63 or later).
Recompile the project from the updated source repository to ensure the corrected code is present if using a custom build.
Limit or quarantine the processing of untrusted BLIF files: run Yosys in a restricted environment or remove BLIF support if not required to reduce the attack surface.

Generated by OpenCVE AI on April 18, 2026 at 10:10 UTC.

Tracking

Advisories

No advisories available

Metrics

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact Low

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact Low

User Interaction None

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact Low

User Interaction None

Access Vector Local

Access Complexity Low

Authentication Single

Confidentiality Impact None

Integrity Impact None

Availability Impact Partial

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.144% probability within 30 days)

Exploitation poc

Automatable no

Technical Impact partial

References

Link	Providers
https://github.com/YosysHQ/yosys/
https://github.com/YosysHQ/yosys/issues/5677
https://github.com/YosysHQ/yosys/pull/5680
https://github.com/YosysHQ/yosys/pull/5681
https://github.com/oneafter/0210/blob/main/yo2/repro
https://vuldb.com/?ctiid.348302
https://vuldb.com/?id.348302
https://vuldb.com/?submit.763755

History

Mar 2, 2026 3:15 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mar 2, 2026 12:15 PM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Yosyshq Yosyshq yosys
Vendors & Products		Yosyshq Yosyshq yosys

Mar 2, 2026 3:15 AM Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		A vulnerability was determined in YosysHQ yosys up to 0.62. This affects the function Yosys::RTLIL::Const::set of the file kernel/rtlil.h of the component BLIF File Parser. This manipulation causes heap-based buffer overflow. It is possible to launch the attack on the local host. The exploit has been publicly disclosed and may be utilized. Applying a patch is the recommended action to fix this issue. It appears that the issue is not reproducible all the time.
Title		YosysHQ yosys BLIF File rtlil.h set heap-based overflow
Weaknesses		CWE-119 CWE-122
References		https://github.com/YosysHQ/yosys/ https://github.com/YosysHQ/yosys/issues/5677 https://github.com/YosysHQ/yosys/pull/5680 https://github.com/YosysHQ/yosys/pull/5681 https://github.com/oneafter/0210/blob/main/yo2/repro https://vuldb.com/?ctiid.348302 https://vuldb.com/?id.348302 https://vuldb.com/?submit.763755
Metrics		cvssV2_0 `{'score': 1.7, 'vector': 'AV:L/AC:L/Au:S/C:N/I:N/A:P/E:POC/RL:OF/RC:C'}` cvssV3_0 `{'score': 3.3, 'vector': 'CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C'}` cvssV3_1 `{'score': 3.3, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C'}` cvssV4_0 `{'score': 4.8, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P'}`

Subscriptions

Yosyshq Yosys

Weaknesses

CWE-119
Improper Restriction of Operations within the Bounds of a Memory Buffer
CWE-122
Heap-based Buffer Overflow

Sources

CVE record Updated: Mar 2, 2026, 2:43 PM

Status: PUBLISHED
Assigner: VulDB
Published: Mar 2, 2026, 3:02 AM
Updated: Mar 2, 2026, 2:43 PM
Reserved: Mar 1, 2026, 7:03 AM

View source JSON

Vulnrichment Updated: Mar 2, 2026, 2:40 PM

Updated: Mar 2, 2026, 2:40 PM

JSON

NVD Updated: Jun 17, 2026, 10:43 AM

Status: Deferred
Published: Mar 2, 2026, 3:16 AM
Modified: Jun 17, 2026, 10:43 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment Updated: Apr 18, 2026, 10:15 AM

Updated: Apr 18, 2026, 10:15 AM

JSON

Analysis

Technical impact

Affected Systems

Risk and Exploitability

Affected Products

Remediation

Tracking

Advisories

Metrics

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact Low

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact Low

User Interaction None

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact Low

User Interaction None

Access Vector Local

Access Complexity Low

Authentication Single

Confidentiality Impact None

Integrity Impact None

Availability Impact Partial

Exploitation poc

Automatable no

Technical Impact partial

Subscriptions

Sources

JSON object

JSON object

JSON object

JSON object

JSON object