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Response snapshot Oct 31, 2026, 00:16 UTC

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VulnerabilityCVE-2026-62958

libriscv is a RISC-V sandbox and emulator.

libriscv is a RISC-V sandbox and emulator. Prior to 1.18, a crafted ELF binary can cause out-of-bounds reads in the host emulator. Memory<W>::binary_loader checks PT_LOAD program-header bounds, but Memory<W>::serialize_execute_segment trusts section-header sh_offset and sh_size when locating .

At a glance

Exploited
Not known
Severity
7.9 High (CVSS 3.1)
Chance of exploitation
Not estimated
Sources
1 source

What to do

Check the vendor advisory for affected versions and fixes.

Read NVD CVE-2026-62958 (opens a new tab)

What happened

libriscv is a RISC-V sandbox and emulator. Prior to 1.18, a crafted ELF binary can cause out-of-bounds reads in the host emulator. Memory<W>::binary_loader checks PT_LOAD program-header bounds, but Memory<W>::serialize_execute_segment trusts section-header sh_offset and sh_size when locating .text without verifying the file range against m_binary.size(); Memory<W>::lookup() has a similar section-table problem.

Malformed .text or .symtab offsets can therefore bypass the program-header checks and point outside the binary buffer, crashing rvlinux. With suitable memory layout or integer overflow, out-of-buffer host heap memory may instead be mapped into the guest by create_execute_segment(), potentially exposing host memory.

The reported reproducer demonstrates a host SIGSEGV, while memory disclosure through grooming is described as possible rather than demonstrated. This issue is fixed in version 1.18.

Scores and how they were measured

CVSS base severity

7.9

Version 3.1As of

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:H

Measurement source (opens a new tab)

How bad it is if exploited. Not a prediction of exploitation or proof you are exposed.

EPSS probability

Not available

A model's estimate of exploitation in the next 30 days, not certainty or your own risk.

Sources

  1. Primary source

    NVD CVE-2026-62958 (opens a new tab)

    NVD record: description, CVSS (the CNA score is preferred), affected products, and publication date. Not evidence of exploitation.

    Published Checked

  2. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  3. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  4. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

Cite this record

For factual claims, cite the primary sources above; cite KEVWire for its compilation, dates, and classifications.

APA

KEVWire. (2026, October 30). libriscv is a RISC-V sandbox and emulator. (CVE-2026-62958). https://kevwire.com/record/CVE-2026-62958

MLA

"libriscv is a RISC-V sandbox and emulator. (CVE-2026-62958)." KEVWire, 30 Oct. 2026, kevwire.com/record/CVE-2026-62958.

Chicago

KEVWire. "libriscv is a RISC-V sandbox and emulator. (CVE-2026-62958)." Last modified October 30, 2026. https://kevwire.com/record/CVE-2026-62958.

Evidence summary (plain text)

libriscv is a RISC-V sandbox and emulator. (Oct 30, 2026).
libriscv is a RISC-V sandbox and emulator. Prior to 1.18, a crafted ELF binary can cause out-of-bounds reads in the host emulator. Memory<W>::binary_loader checks PT_LOAD program-header bounds, but Memory<W>::serialize_execute_segment trusts section-header sh_offset and sh_size when locating .text without verifying the file range against m_binary.size(); Memory<W>::lookup() has a similar section-table problem. Malformed .text or .symtab offsets can therefore bypass the program-header checks and point outside the binary buffer, crashing rvlinux.
CVSS 7.9 (version 3.1; evidence as of Oct 30, 2026; https://nvd.nist.gov/vuln/detail/CVE-2026-62958).
Sources:
NVD CVE-2026-62958: https://nvd.nist.gov/vuln/detail/CVE-2026-62958
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-30T20:56:01.746Z&lastModEndDate=2026-10-30T22:30:56.395Z&resultsPerPage=500&startIndex=0
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-30T20:20:59.645Z&lastModEndDate=2026-10-30T21:55:57.278Z&resultsPerPage=500&startIndex=0
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-30T19:46:09.038Z&lastModEndDate=2026-10-30T21:20:56.675Z&resultsPerPage=500&startIndex=0
Record ID: CVE-2026-62958.
Record origin: Ingested record.
AI evidence: Not assessed.
Known exploitation: Not assessed.
Zero-day status: Not assessed. KEV membership alone does not establish zero-day status.
About this data

This record was ingested from a data source. Retrieved: Oct 30, 2026, 22:30 UTC. Ingestion is not an independent editorial investigation.

NVD status: Received. Publication in the NVD is not evidence of exploitation.

A CISA KEV listing documents known exploitation, not necessarily a zero-day; absence from the catalog does not prove a vulnerability has never been exploited.

Technology tags indicate possible relevance, not verified exposure. Confirm the affected product, version, and configuration against your own inventory; KEVWire does not scan your systems.

A personal reading checklist on this device, not verified remediation.

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Record details

Record detail