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NVD / CVE Program· CNA GitHub_M

CVE-2025-67873: Capstone doesn't check Skipdata length, leading to cs_insn.bytes heap buffer overflow

Noroxi assessment

Priority: Monitor (action score 31/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.23% (FIRST EPSS).
  • Someone with local access to the system can trigger it. No account or password is required. A user must open a link or visit a page. No special conditions are required; it is repeatable.
  • Fixed version: capstone-java (AlmaLinux:10) 5.0.1-7.el10_1; python3-capstone (AlmaLinux:10) 5.0.1-7.el10_1; capstone (AlmaLinux:9) 4.0.2-11.el9_7.
  • Severity is disputed: the assigning authority (CNA) scores it 4.8, NVD 7.8.

Low priority for now. Upgrade to capstone-java (AlmaLinux:10) 5.0.1-7.el10_1; python3-capstone (AlmaLinux:10) 5.0.1-7.el10_1; capstone (AlmaLinux:9) 4.0.2-11.el9_7 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Capstone is a disassembly framework. In versions 6.0.0-Alpha5 and prior, Skipdata length is not bounds-checked, so a user-provided skipdata callback can make cs_disasm/cs_disasm_iter memcpy more than 24 bytes into cs_insn.bytes, causing a heap buffer overflow in the disassembly path. Commit cbef767ab33b82166d263895f24084b75b316df3 fixes the issue.

HighCVSS 7.8 · v3.1—No exploit Fix available
Published
Dec 17, 2025
Updated
Oct 13, 2026
EPSS
0.2% · 14th percentile

Report tools

JSON

Action score

31

Monitor

Low priority for now.

CVSS
31 / 40 · 7.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
7.8
CNA · GitHub_M
4.8
3.0 point gap

CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2025-67873

When you'll hear from us

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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
capstone-enginecapstone

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • capstone-engine capstonebefore 6.0.0
  • capstone-engine capstone6.0.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • capstone-engine capstone

    • <= 6.0.0-Alpha5affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:10capstone-javabefore 5.0.1-7.el10_15.0.1-7.el10_1
AlmaLinux:10python3-capstonebefore 5.0.1-7.el10_15.0.1-7.el10_1
AlmaLinux:9capstonebefore 4.0.2-11.el9_74.0.2-11.el9_7
AlmaLinux:9capstone-develbefore 4.0.2-11.el9_74.0.2-11.el9_7
AlmaLinux:9capstone-javabefore 4.0.2-11.el9_74.0.2-11.el9_7
AlmaLinux:9python3-capstonebefore 4.0.2-11.el9_74.0.2-11.el9_7
Debian:12capstonefrom 0—
Debian:13capstonebefore 5.0.7-1~deb13u15.0.7-1~deb13u1
Debian:14capstonebefore 5.0.7-15.0.7-1
openSUSE:Leap 15.6capstonebefore 4.0.2-150500.3.3.14.0.2-150500.3.3.1
Red Hat:enterprise_linux_eus:10.0capstonebefore 0:5.0.1-7.el10_00:5.0.1-7.el10_0
Red Hat:enterprise_linux_eus:10.0capstone-debuginfobefore 0:5.0.1-7.el10_00:5.0.1-7.el10_0
Red Hat:enterprise_linux_eus:10.0capstone-debugsourcebefore 0:5.0.1-7.el10_00:5.0.1-7.el10_0
Red Hat:enterprise_linux_eus:10.0capstone-develbefore 0:5.0.1-7.el10_00:5.0.1-7.el10_0
Red Hat:enterprise_linux_eus:10.0capstone-javabefore 0:5.0.1-7.el10_00:5.0.1-7.el10_0
Red Hat:enterprise_linux_eus:10.0python3-capstonebefore 0:5.0.1-7.el10_00:5.0.1-7.el10_0
Red Hat:enterprise_linux:10.1capstonebefore 0:5.0.1-7.el10_10:5.0.1-7.el10_1
Red Hat:enterprise_linux:10.1capstone-debuginfobefore 0:5.0.1-7.el10_10:5.0.1-7.el10_1
Red Hat:enterprise_linux:10.1capstone-debugsourcebefore 0:5.0.1-7.el10_10:5.0.1-7.el10_1
Red Hat:enterprise_linux:10.1capstone-develbefore 0:5.0.1-7.el10_10:5.0.1-7.el10_1
Red Hat:enterprise_linux:10.1capstone-javabefore 0:5.0.1-7.el10_10:5.0.1-7.el10_1
Red Hat:enterprise_linux:10.1python3-capstonebefore 0:5.0.1-7.el10_10:5.0.1-7.el10_1
Red Hat:enterprise_linux:9::appstreamcapstonebefore 0:4.0.2-11.el9_70:4.0.2-11.el9_7
Red Hat:enterprise_linux:9::appstreamcapstone-debuginfobefore 0:4.0.2-11.el9_70:4.0.2-11.el9_7

+37

Same product

capstone-engine: all records

Other highest-scoring records for the same primary product.

  • CVE-2025-68114Capstone doesn't check vsnprintf return in SStream_concat, allows stack buffer underflow and overflow
    39Monitor
  • CVE-2017-6952Integer overflow in the cs_winkernel_malloc function in winkernel_mm.c in Capstone 3.0.4 and earlier allows attackers to cause a denial of s
    35Monitor
  • CVE-2026-55893Capstone SH disassembler `set_reg_n` heap buffer overflow via crafted SH2A FPU bytecode
    29Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2016-7151May 15, 2019 · Capstone 3.0.4 has an out-of-bounds vulnerability (SEGV caused by a read memory access) in X86_insn_reg_intel in arch/X86/X86Mapping.c.
    22Monitor
  • Later →CVE-2026-47143Jul 21, 2026 · Capstone has a NULL Pointer Dereference with 3DNow! opcodes
    23Monitor
  • Later →CVE-2026-49263Aug 14, 2026 · Capstone WASM `br_table` instruction-size truncation can cause no-progress disassembly and parser desynchronization
    8Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
almalinux:capstone4.0.2-11.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:capstone-devel4.0.2-11.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:capstone-java4.0.2-11.el9_7 · AlmaLinux:9Package registry (OSV)
almalinux:python3-capstone4.0.2-11.el9_7 · AlmaLinux:9Package registry (OSV)
debian:capstone5.0.7-1~deb13u1 · Debian:13Package registry (OSV)
opensuse:capstone4.0.2-150500.3.3.1 · openSUSE:Leap 15.6Package registry (OSV)
red hat:capstone0:5.0.7-0.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:capstone-debuginfo0:4.0.2-5.el9_0 · Red Hat:rhel_e4s:9.0::appstreamPackage registry (OSV)
red hat:capstone-debugsource0:4.0.2-5.el9_0 · Red Hat:rhel_e4s:9.0::appstreamPackage registry (OSV)
red hat:capstone-devel0:4.0.2-11.el9_7 · Red Hat:enterprise_linux:9::crbPackage registry (OSV)
red hat:capstone-devel0:5.0.7-0.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:capstone-java0:5.0.7-0.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:capstone-static0:5.0.7-0.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:python3-capstone0:4.0.2-11.el9_7 · Red Hat:enterprise_linux:9::crbPackage registry (OSV)
red hat:python3-capstone0:5.0.7-0.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:python3-capstone-debuginfo0:4.0.2-5.el9_0 · Red Hat:rhel_e4s:9.0::appstreamPackage registry (OSV)
rocky linux:capstone0:4.0.2-11.el9_7 · Rocky Linux:9Package registry (OSV)
suse:capstone4.0.2-150500.3.3.1 · SUSE:Linux Enterprise Micro 5.5Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-55893246 days apartCapstone SH disassembler `set_reg_n` heap buffer overflow via crafted SH2A FPU bytecode
    29Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • No account or password is required.
  • A user must open a link or visit a page.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-122 · Heap-based Buffer Overflow

CVSS vector

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

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records