VulnerabilityPublished 14 Dec 2025Updated 15 Dec 2025

CVE-2025-67899: uriparser · Uncontrolled Recursion

Affects uriparserSource CVE Database V5

Not known to be exploited · CVSS 2.9 Low.

Data as of 26 Oct 2026, 17:16 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 14 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

Affected software

Product	Affected	Fixed in
uriparser project uriparser	Affected =0	Fixed in–

AI-suggested

To mitigate CVE-2025-67899, European organizations should: 1) Identify all software components and systems using uriparser, especially versions up to 0.9.9. 2) Implement strict input validation and sanitization to limit the size and complexity of URI inputs, particularly restricting the number of commas or segment delimiters processed locally. 3) Employ runtime protections such as stack size limits or recursion depth monitoring where possible to prevent stack overflow conditions. 4) Monitor vendor and open-source project updates for patches addressing this vulnerability and plan timely upgrades once available. 5) Conduct code reviews and static analysis on custom software integrating uriparser to detect unsafe recursion patterns. 6) Limit local access to systems processing untrusted URI inputs to reduce attack surface. 7) Consider alternative URI parsing libraries with better resilience to malformed input if feasible. These steps go beyond generic advice by focusing on local input controls, software inventory, and proactive monitoring tailored to the nature of this vulnerability.

Description

uriparser through 0.9.9 allows unbounded recursion and stack consumption, as demonstrated by ParseMustBeSegmentNzNc with large input containing many commas.

Impact

The primary impact of CVE-2025-67899 is a denial of service caused by stack overflow due to uncontrolled recursion in the uriparser library. For European organizations, this could disrupt local applications or embedded systems that rely on uriparser for URI parsing, particularly if they process untrusted or malformed input containing many commas. While the vulnerability does not compromise confidentiality or integrity, availability interruptions could affect critical systems, especially in sectors like manufacturing, telecommunications, or software development where uriparser might be embedded. The local attack vector and high complexity reduce the likelihood of widespread exploitation, but insider threats or compromised local users could trigger the issue. Organizations with automated URI processing pipelines or custom software using uriparser should be cautious. The lack of known exploits and patches means the threat is currently theoretical but should be addressed proactively to avoid future exploitation. Overall, the impact is low but non-negligible in environments where availability is critical.

CWE-674Uncontrolled Recursion (opens in a new tab)
Class weakness
The product does not properly control the amount of recursion that takes place, consuming excessive resources, such as allocated memory or the program stack.
Implementation
Ensure that an end condition will be reached under all logic conditions. The end condition may include checking against the depth of recursion and exiting with an error if the recursion goes too deep. The complexity of the end condition contributes to the effectiveness of this action.
Implementation
Increase the stack size.
Attack patterns
Serialized Data with Nested Payloads (opens in a new tab)
Oversized Serialized Data Payloads (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 21 Dec 2025, 23:33 UTC

WeaknessesCWE-674

Technical details

References

Community reviews

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