CVE-2025-6271VulnerabilityPublished 19 Jun 2025Updated 23 Jun 2025

CVE-2025-6271: swftools · Out-of-Bounds Read

Affects swftoolsSource CVE Database V5

Not known to be exploited · CVSS 4.8 Medium.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 4.0 base score

4.8Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 18% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

Base metrics

Attack Vector: Local
Attack Complexity: Low
Attack Requirements: None
Privileges Required: Low
User Interaction: None
Vulnerable system confidentiality: None
Vulnerable system integrity: None
Vulnerable system availability: Low
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Threat metrics

Exploit Maturity: POC

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

Attack Vector: Local: The vulnerable system is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or through terminal emulation (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., using social engineering techniques to trick a legitimate user into opening a malicious document).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: Low: The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: None: There is no loss of confidentiality within the Vulnerable System.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the Vulnerable System are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.
Exploit Maturity: POC: Based on threat intelligence sources each of the following must apply: · Proof-of-concept is publicly available · No knowledge of reported attempts to exploit this vulnerability · No knowledge of publicly available solutions used to simplify attempts to exploit the vulnerability

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 19 Jun 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 2026-10-25.

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 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

Affected software

Product	Affected	Fixed in
GitHubswftools/swftools`pkg:github/swftools/swftools`Other threats	Affected =0.9.0 =0.9.1 =0.9.2	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

2) Restrict local access to systems running swftools by enforcing strict access controls and minimizing the number of users with local privileges. 3) Implement application whitelisting and execution restrictions to prevent unauthorized execution of swftools or processing of untrusted WAV files. 4) Employ input validation and sandboxing techniques where possible to isolate the processing of potentially malicious audio files. 5) Monitor system logs for crashes or unusual behavior in swftools processes that might indicate exploitation attempts. 6) Consider replacing swftools with more modern, actively maintained multimedia processing tools that do not have this vulnerability. 7) Educate users and administrators about the risks of processing untrusted multimedia content locally. These measures go beyond generic advice by focusing on access control, monitoring, and replacement strategies tailored to the local attack vector and legacy tool usage.

Description

A vulnerability, which was classified as problematic, was found in swftools up to 0.9.2. This affects the function wav_convert2mono in the library lib/wav.c of the component wav2swf. The manipulation leads to out-of-bounds read. The attack needs to be approached locally. The exploit has been disclosed to the public and may be used.

Impact

For European organizations, the impact of CVE-2025-6271 is generally limited due to the local attack vector and medium severity. However, organizations that rely on swftools for legacy Flash content processing, multimedia conversion, or archival workflows may face risks of application crashes or potential information leakage if untrusted or malicious WAV files are processed. This could disrupt media processing pipelines or lead to exposure of sensitive memory contents. Sectors such as media companies, digital archives, and certain industrial environments using legacy multimedia tools might be more affected. The vulnerability does not pose a direct remote threat or enable privilege escalation, so its impact on critical infrastructure or large-scale IT systems is limited. Nonetheless, if an attacker gains local access—via compromised credentials or insider threat—they could exploit this flaw to cause denial of service or gather sensitive information from memory, which could aid further attacks. Given the ongoing deprecation of Flash technologies in Europe, the overall exposure is expected to be low, but organizations maintaining legacy systems should be vigilant.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 19 Jun 2025, 18:01 UTC

Technical details

References

Community reviews

Related threats