Auth bypass in Spaceapplications Yamcs
CVE-2026-55548
Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, the PacketsApi.exportPackets endpoint in yamcs-core/src/main/java/org/yamcs/http/api/PacketsApi.java failed to enforce object-level ReadPacket privileges when a request omitted specific packet names: with an empty name list the ctx.checkObjectPrivileges(ObjectPrivilegeType.ReadPacket, nameSet) call passed over an empty set, no WHERE pname IN filter was applied to the resulting SELECT * FROM tm query, and the onTuple handler streamed every retrieved packet without any per-row authorization check, so a low-privileged or zero-privilege authenticated user could dump the entire raw telemetry packet archive and bypass the role-based access control model. This issue is fixed in versions 5.12.8 and 5.13.2, which enforce per-packet ReadPacket checks in exportPackets.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.004 (28.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 28.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Spaceapplications Yamcs
- Yamcs — versions < 5.12.8, >= 5.13.0, < 5.13.2
Weakness classification (CWE)
References
- github.com/yamcs/yamcs/security/advisories/GHSA-8xjq-pr36-ccgf (Exploit, Mitigation, Vendor Advisory)
- github.com/yamcs/yamcs/commit/b566beceba98cc35514b0e1519be126b8c5a0438 (Patch)
- github.com/yamcs/yamcs/commit/c743cc3acf5b5c53ff5181b94eacc21340f70dd9 (Patch)
- github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8 (Release Notes)
- github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2 (Release Notes)
Frequently asked questions
- What is CVE-2026-55548?
- CVE-2026-55548 is a medium-severity vulnerability in Spaceapplications Yamcs, classified under Improper Access Control. CVSS score: 4.3/10. Published 2026-07-16.
- How severe is CVE-2026-55548?
- Medium severity. CVSS v3 base score is 4.3 out of 10.