CVE-2025-66865Public exploit

Process crash via recursive demangler stack exhaustion

Published Dec 29, 2025 · Updated Dec 29, 2025

Stack overflow in GNU Binutils 2.26 c++filt allows attackers to crash the utility by processing a crafted PE file. The d_print_comp_inner routine in libiberty/cp-demangle.c recursively formats attacker-controlled demangling structures until the process stack is exhausted. The file must be passed to c++filt, and the demonstrated consequence is process termination rather than code execution or data access.

CVSS severity7.5
High
EPSS probability0.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack overflow in GNU Binutils 2.26 c++filt allows attackers to crash the utility by processing a crafted PE file. The d_print_comp_inner routine in libiberty/cp-demangle.c recursively formats attacker-controlled demangling structures until the process stack is exhausted. The file must be passed to c++filt, and the demonstrated consequence is process termination rather than code execution or data access.

The record

CVE
CVE-2025-66865
Published
Dec 29, 2025
Updated
Dec 29, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-121
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 29, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 29, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5UbuntuCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-121Stack-based Buffer Overflow

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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