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Fencer Intel
high 7.9

CVE-2026-62958 json

libriscv: Out of bounds read vuln in the ELF parser (Denial of service)

published 4mo ago modified 9d ago also EUVD-2026-114467 , GHSA-gm4g-6c78-gr3w

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository libriscv/libriscv. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
7.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 10%
public exploits
0
none known

Summary

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.

Patch / fix

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
9d ago

Exploit prediction

0.21% chance of exploitation in the next 30 days, higher than 10% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/libriscv/libriscv/security/advisories/GHSA-gm4g-6c78-gr3w referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 7.9 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:H

Affected products

  • libriscv libriscv

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of libriscv/libriscv published their own advisory on GitHub. Reviewed sources take precedence over it.