VulnerabilityPublished 28 Apr 2026

CVE-2026-33467: Elastic Package Registry · Improper Verification of Cryptographic Signature

Affects Elastic Package RegistrySource CVE Database V5

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Not known to be exploited · CVSS 5.9 Medium.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

5.9Medium

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:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

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

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: 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: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 28 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 30 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.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), 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
ElasticElastic Package Registry	Affected >=0.1.0 <=1.37.0	Fixed in–

Description

CVE-2026-33467 is a medium severity vulnerability in Elastic Package Registry version 0.1.0 involving improper verification of cryptographic signatures (CWE-347). This flaw could allow an attacker who can intercept network traffic or influence the contents served by a self-hosted registry to substitute a tampered package without triggering an integrity check failure. There is no official patch or remediation level provided by the vendor at this time, and no known exploits in the wild have been reported. The vulnerability impacts the integrity of packages distributed via the affected registry version.

Impact

An attacker able to intercept or manipulate network traffic to a self-hosted Elastic Package Registry could substitute malicious or tampered packages without detection due to improper cryptographic signature verification. This compromises the integrity of packages delivered to users relying on the registry, potentially leading to the installation of unauthorized or malicious code. There is no impact on confidentiality or availability reported. No known exploits have been observed in the wild.

Summary

The vulnerability CVE-2026-33467 affects Elastic Package Registry version 0.1.0 and is categorized under CWE-347 (Improper Verification of Cryptographic Signature). It allows an attacker positioned to intercept network traffic or influence the self-hosted registry contents to replace a package with a tampered one without the integrity verification failing. This undermines the trustworthiness of package distribution by the registry. The CVSS v3.1 base score is 5.9 (medium severity), with network attack vector, high attack complexity, no privileges required, no user interaction, unchanged scope, no confidentiality impact, high integrity impact, and no availability impact.

CWE-347Improper Verification of Cryptographic Signature (opens in a new tab)
Base weaknessOWASP Top 10 A04:2025: Cryptographic Failures (opens in a new tab)
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
OWASP Cheat Sheets
XML Security (opens in a new tab)
REST Security (opens in a new tab)
JSON Web Token for Java (opens in a new tab)
REST Assessment (opens in a new tab)
Cross-Site Request Forgery Prevention (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.2 (opens in a new tab)
V3.5.3 (opens in a new tab)
V13.2.6 (opens in a new tab)
Attack patterns
Padding Oracle Crypto Attack (opens in a new tab)
Signature Spoofing by Improper Validation (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

discuss.elastic.co/t/elastic-package-registry-1-38-0-security-update-esa-2026-27/386081 (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 6 May 2026, 02:13 UTC

WeaknessesCWE-347

Technical details

References

Community reviews

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