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Fencer Intel
medium 5.1

CVE-2026-49282 json

Capstone M68K and RISCV `cs_insn_name()` invalid IDs can trigger out-of-bounds reads and process crashes

published 5mo ago modified last mo. also EUVD-2026-58744 , GHSA-jrw4-wj52-2vw8

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository capstone-engine/capstone. 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
5.1
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 7%
public exploits
0
none known

Summary

Capstone is a disassembly framework. Prior to version 6.0.0-Alpha9, Capstone's public `cs_insn_name()` API forwards caller-supplied instruction IDs directly to the selected architecture backend. Most backends validate the ID before indexing instruction-name tables, but the M68K and RISCV backends have missing or incomplete bounds checks. On a Capstone handle opened for M68K or RISCV, a caller-controlled invalid instruction ID can trigger an out-of-bounds read and crash the process. The demonstrated impact is availability loss in applications or bindings that expose instruction-name lookup to untrusted IDs. No code execution or data disclosure was demonstrated. Version 6.0.0-Alpha9 patches the issue.

Patch / fix

  • capstone-engine capstone 6.0.0-alpha9
  • capstone hummingbird 1 5.0.8-0.5.hum1
  • capstone-java hummingbird 1 5.0.8-0.5.hum1
  • python3-capstone hummingbird 1 5.0.8-0.5.hum1

red hat advisories RHSA-2026:81540

  • rust Azure Linux 3.0 1.75.0-30
  • rust Azure Linux 3.0 1.90.0-10

azure linux advisories AZL-96737AZL-96746

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-49282 updated cvss 6.2

capstone: Capstone: Denial of service via out-of-bounds read in M68K and RISCV backends

  • Red Hat Enterprise Linux 9 capstone, capstone-java, python3-capstone Red Hat Enterprise Linux 10 capstone
    affected: no fix planned “Will not fix”
  • Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9
    affected: no fix available “Fix deferred”
  • Red Hat Hardened Images capstone 5.0.8-0.5.hum1, capstone-java 5.0.8-0.5.hum1, python3-capstone 5.0.8-0.5.hum1
    fixed: vendor fix RHSA-2026:81540

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
2mo ago

Exploit prediction

0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/capstone-engine/capstone/security/advisories/GHSA-jrw4-wj52-2vw8 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 5.1 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L

Affected products

  • capstone-engine capstone

Classification

Weakness
  • CWE-125 Out-of-bounds Read
  • CWE-129 Improper Validation of Array Index
  • CWE-191 Integer Underflow (Wrap or Wraparound)

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 capstone-engine/capstone published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.