CVE-2025-45525VulnerabilityPublished 17 Jun 2025Updated 26 Aug 2025

CVE-2025-45525: asvd microlight · NULL Pointer Dereference

Affects asvd microlightSource CVE Database V5

Not known to be exploited · CVSS 2.9 Low.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

2.9Low

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

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

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

Attack Vector: Local: The vulnerable component 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 remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
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: 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 impacted component 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 impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 17 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
npmmicrolight`pkg:npm/microlight`Other threats	Affected =0	Fixed in–

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

AI-suggested

To mitigate this vulnerability, European organizations should first identify any usage of microlight version 0.0.7 within their web applications or internal tools. Developers can implement wrapper functions that validate CSS color inputs against a whitelist of standard formats before passing them to microlight. Additionally, error handling should be enhanced to catch and gracefully manage exceptions arising from unexpected input, preventing application crashes. Organizations should monitor updates from the microlight project or vendor for official patches or fixes. Where feasible, consider replacing microlight with alternative syntax highlighting libraries that have a more robust input validation mechanism. Finally, conduct thorough testing of web applications to simulate edge cases involving CSS color inputs to ensure stability and resilience against malformed data.

Description

A NULL pointer dereference vulnerability has been identified in the JavaScript library microlight version 0.0.7, a lightweight syntax highlighting library. When processing elements with non-standard CSS color values, the library fails to validate the result of a regular expression match before accessing its properties, leading to an uncaught TypeError and potential application crash. NOTE: this is disputed by multiple parties because there is no common scenario in which an adversary can insert those non-standard values.

Impact

For European organizations, the impact of this vulnerability is generally low. Since microlight is a niche JavaScript library used for syntax highlighting, its deployment is mostly limited to web applications or developer tools that require lightweight code display features. The primary risk is a denial of service caused by application crashes when processing malformed or unexpected CSS color inputs. This could disrupt user experience or internal workflows but is unlikely to result in data loss or unauthorized access. Organizations relying on microlight in internal developer portals, documentation sites, or code review tools might experience temporary outages or degraded service availability. Given the disputed nature of the vulnerability and the lack of known exploitation methods, the threat to European enterprises is minimal. However, organizations with high availability requirements or those operating critical web services that incorporate microlight should consider the potential for service disruption. The vulnerability does not pose a direct threat to confidentiality or integrity of data, reducing the overall risk profile for sensitive environments.

CWE-476NULL Pointer Dereference (opens in a new tab)
Base weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #13OWASP Top 10 A10:2025: Mishandling of Exceptional Conditions (opens in a new tab)
The product dereferences a pointer that it expects to be valid but is NULL.
Implementation
For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
Requirements
Select a programming language that is not susceptible to these issues.
Implementation
Check the results of all functions that return a value and verify that the value is non-null before acting upon it.
OWASP Cheat Sheets
Logging (opens in a new tab)
Error Handling (opens in a new tab)
OWASP ASVS 4.0.3
V11.1.7 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 27 Aug 2025, 00:41 UTC

WeaknessesCWE-476

Technical details

References

Community reviews

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