CVE-2026-25140VulnerabilityPublished 4 Feb 2026

CVE-2026-25140: chainguard-dev apko · Uncontrolled Resource Consumption

Affects chainguard-dev apkoSource CVE Database V5

Not known to be exploited · CVSS 7.5 High : upgrade to 1.1.1 soon.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

7.5High

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 35% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 1.1.1

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 4 Feb 2026
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 apko and chainguard-dev/apko to 1.1.1.

Affected software

Product	Affected	Fixed in
chainguard-devapko	Affected >=0.14.8 <1.1.1	Fixed in 1.1.1
GitHubchainguard-dev/apko`pkg:github/chainguard-dev/apko`Other threats	Affected >=0.14.8 <1.1.1	Fixed in 1.1.1

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

AI-suggested

To mitigate CVE-2026-25140, organizations should upgrade all instances of apko to version 1.1.1 or later, where the vulnerability has been patched. Additionally, organizations should implement strict validation and vetting of APK repositories used in their build pipelines to prevent supply chain compromise. Employing repository whitelisting, cryptographic signing verification, and integrity checks on APK packages can reduce the risk of malicious inputs. Monitoring resource usage during container builds and setting resource limits or quotas on build hosts can help detect and prevent resource exhaustion attacks. Integrating anomaly detection in CI/CD pipelines to flag unusually large decompression sizes or build failures can provide early warning. Finally, organizations should consider isolating build environments and using ephemeral build hosts to limit the blast radius of potential attacks.

Description

apko allows users to build and publish OCI container images built from apk packages. From version 0.14.8 to before 1.1.1, an attacker who controls or compromises an APK repository used by apko could cause resource exhaustion on the build host. The ExpandApk function in pkg/apk/expandapk/expandapk.go expands .apk streams without enforcing decompression limits, allowing a malicious repository to serve a small, highly-compressed .apk that inflates into a large tar stream, consuming excessive disk space and CPU time, causing build failures or denial of service. This issue has been patched in version 1.1.1.

Impact

For European organizations, the impact of CVE-2026-25140 can be significant, particularly for those relying on apko for container image builds in CI/CD pipelines or production environments. Resource exhaustion on build hosts can lead to denial of service, delaying software delivery and potentially causing downtime in development or deployment workflows. Organizations using third-party or less trusted APK repositories are at higher risk of supply chain attacks that exploit this vulnerability. The disruption can affect availability of containerized applications, impacting business continuity and operational efficiency. Additionally, the consumption of excessive CPU and disk resources may increase operational costs and complicate incident response. While confidentiality and integrity are not directly impacted, the availability impact alone can be critical in environments with tight deployment schedules or automated pipelines. European sectors with high container adoption, such as finance, manufacturing, and technology, may face operational risks if this vulnerability is exploited.

CWE-400Uncontrolled Resource Consumption (opens in a new tab)
Class weaknessLikelihood of exploit: High
The product does not properly control the allocation and maintenance of a limited resource.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
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. A strong authentication and access control model will help prevent such attacks from occurring in the first place.
Architecture and Design
Mitigation of resource exhaustion attacks requires that the target system either: recognizes the attack and denies that user further access for a given amount of time, or; uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed.
Architecture and Design
Ensure that protocols have specific limits of scale placed on them.
OWASP Cheat Sheets
File Upload (opens in a new tab)
OWASP ASVS 4.0.3
V12.1.1 (opens in a new tab)
Attack patterns
XML Ping of the Death (opens in a new tab)
Regular Expression Exponential Blowup (opens in a new tab)
Sustained Client Engagement (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 4 Feb 2026, 19:29 UTC

WeaknessesCWE-400

Technical details

References

Community reviews

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