CVE-2025-29606VulnerabilityPublished 14 Jul 2025

CVE-2025-29606: py-libp2p · Unthrottled Resource Allocation

Affects py-libp2pSource CVE Database V5

Not known to be exploited · CVSS 4.3 Medium : upgrade to 0.2.3 when convenient.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

4.3Medium

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.
Patch: Available – fixed in 0.2.3

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
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: 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: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
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 Jul 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 2026-10-26.

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

Upgrade py-libp2p to 0.2.3.

Affected software

Product	Affected	Fixed in
PyPIpy-libp2p`pkg:pypi/py-libp2p`Other threats	Affected <0.2.3	Fixed in 0.2.3

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

AI-suggested

European organizations should immediately audit their use of py-libp2p and identify any deployments running versions prior to 0.2.3. If you cannot patch yet, organizations can implement network-level controls to limit the size and rate of RSA key submissions from peers, effectively throttling resource-intensive requests. Deploying application-layer rate limiting and input validation to reject abnormally large keys can mitigate exploitation attempts. Monitoring resource utilization metrics on nodes running py-libp2p can help detect anomalous spikes indicative of an attack. Additionally, isolating critical nodes behind firewalls or VPNs to restrict peer access reduces exposure. Organizations should stay alert for official patches or updates from the py-libp2p project and apply them promptly once available. Incorporating this vulnerability into incident response playbooks and threat hunting activities will improve readiness. Finally, engaging with the open-source community for updates and best practices around secure libp2p usage is recommended.

Description

py-libp2p before 0.2.3 allows a peer to cause a denial of service (resource consumption) via a large RSA key.

Impact

For European organizations leveraging decentralized applications or services that incorporate py-libp2p for peer-to-peer networking, this vulnerability presents a risk of denial of service attacks. Such attacks could disrupt critical communication channels in distributed systems, impacting availability and reliability. Sectors relying on blockchain technologies, distributed file storage, or decentralized identity solutions may be particularly affected. The DoS could lead to service outages, degraded user experience, and potential cascading failures in interconnected systems. Although the vulnerability does not compromise data confidentiality or integrity, the availability impact could hinder operational continuity, especially in environments where high uptime is essential. Given the increasing adoption of decentralized technologies in Europe, the threat could affect financial services, supply chain management, and IoT deployments that utilize py-libp2p. The lack of known exploits reduces immediate risk, but the ease of exploitation (no user interaction required) means attackers could weaponize this vulnerability once exploit code becomes available.

CWE-770Allocation of Resources Without Limits or Throttling (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #25
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
Requirements
Clearly specify the minimum and maximum expectations for capabilities, and dictate which behaviors are acceptable when resource allocation reaches limits.
Architecture and Design
Limit the amount of resources that are accessible to unprivileged users. Set per-user limits for resources. Allow the system administrator to define these limits. Be careful to avoid CWE-410.
Architecture and Design
Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
OWASP ASVS 4.0.3
V8.1.4 (opens in a new tab)
V13.4.1 (opens in a new tab)
V11.1.4 (opens in a new tab)
Attack patterns
XML Ping of the Death (opens in a new tab)
Exponential Data Expansion (opens in a new tab)
Serialized Data Parameter Blowup (opens in a new tab)
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 14 Jul 2025, 04:46 UTC

WeaknessesCWE-770

Technical details

References

Community reviews

Related threats