VulnerabilityPublished 29 Dec 2025Updated 30 Dec 2025

CVE-2025-66865: BinUtils · Stack-based Buffer Overflow

Source CVE Database V5

Not known to be exploited · CVSS 7.5 High.

Data as of 26 Oct 2026, 12:55 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 29 Dec 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

Immediately audit development and build environments to identify use of BinUtils version 2.26.
Avoid processing untrusted or unauthenticated PE files with the vulnerable BinUtils version.
Implement sandboxing or containerization for build processes to isolate potential crashes and limit impact.
Monitor official GNU BinUtils repositories and security advisories for patches addressing CVE-2025-66865 and apply updates promptly once available.
Where possible, upgrade to a newer, unaffected version of BinUtils after thorough testing.
Integrate input validation and filtering mechanisms to detect and block malformed PE files before they reach BinUtils tools.
Enhance logging and monitoring around build systems to detect abnormal crashes or service interruptions indicative of exploitation attempts.
Educate development teams about the vulnerability and enforce strict controls on the sources of PE files used in builds.
Consider implementing redundancy in build infrastructure to maintain availability during potential DoS incidents.
Coordinate with software supply chain partners to ensure they are aware of and mitigating this vulnerability.

Description

An issue was discovered in function d_print_comp_inner in file cp-demangle.c in BinUtils 2.26 allows attackers to cause a denial of service via crafted PE file.

Impact

For European organizations, the primary impact of CVE-2025-66865 is operational disruption due to denial of service in development and build environments using BinUtils 2.26. Organizations involved in software development, particularly those cross-compiling or analyzing Windows PE files, may experience build failures or interruptions, potentially delaying software delivery and impacting productivity. Critical infrastructure or industries relying on continuous integration/continuous deployment (CI/CD) pipelines that incorporate BinUtils could face downtime or degraded service availability. While the vulnerability does not compromise data confidentiality or integrity, the availability impact can cascade into broader operational challenges, especially in tightly scheduled or automated environments. Additionally, organizations lacking timely patch management processes may remain exposed longer, increasing risk. The absence of known exploits reduces immediate threat but does not eliminate the risk of future exploitation. European entities with stringent uptime requirements or regulatory obligations around software reliability should prioritize mitigation to avoid compliance issues or reputational damage.

CWE-121Stack-based Buffer Overflow (opens in a new tab)
Variant weaknessLikelihood of exploit: HighCWE Top 25 (2025): #14
A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
Operation · Build and Compilation · Environment Hardening
Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index…
Architecture and Design
Use an abstraction library to abstract away risky APIs. Not a complete solution.
Implementation
Implement and perform bounds checking on input.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

github.com/caozhzh/CRGF-Vul/blob/main/cxxfilt/crash4.md (opens in a new tab)

Community reviews

Loading reviews…

Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 30 Dec 2025, 22:48 UTC

WeaknessesCWE-121

Technical details

References

Community reviews

Related threats