Is CVE-2025-30156 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2025-30156 being exploited in the wild.

How severe is CVE-2025-30156?

High severity, with a CVSS score of 8.9, published 28 August 2026.

Is there a fix for CVE-2025-30156?

A patch was published on 2026: Fixed in Ceph 20.2.4 and 19.2.6 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2025-30156 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2025-30156?

Check whether you run Ceph at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2025-30156: Ceph CephX authentication credential forgery via unauthenticated encryption

CVE-2025-30156 · Severity: high · CVSS 8.9 · Published 2026-08-28

Ceph is a distributed storage platform used by organizations to store and manage large volumes of data across multiple servers. A weakness in Ceph's authentication protocol allows attackers with network visibility and low-level access to forge administrator credentials, bypass access controls, and potentially gain complete control over the storage cluster and all data within it.

Technologies: Ceph. Vendors: Ceph.

Quick answers

Is CVE-2025-30156 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2025-30156 being exploited in the wild.
How severe is CVE-2025-30156?: High severity, with a CVSS score of 8.9, published 28 August 2026.
Which products and versions are affected?: Ceph before 20.2.4 and 19.2.6.
Is there a fix for CVE-2025-30156?: A patch was published on 2026: Fixed in Ceph 20.2.4 and 19.2.6 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2025-30156 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2025-30156?: Check whether you run Ceph at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The CephX authentication protocol in Ceph versions before 20.2.4 and 19.2.6 uses AES-128-CBC encryption with a hard-coded initialization vector (IV) and no message authentication code (MAC) to protect authentication tickets. This allows multiple attacks: (1) credential forgery via an encryption oracle attack—an attacker observing encrypted tickets can splice ciphertext blocks to create valid tickets for privileged entities like Manager, MDS, and OSD nodes; (2) privilege escalation by flipping a single bit in an encrypted ticket to set the allow_all flag, granting unrestricted cluster access. The attack requires network access to observe CephX traffic and possession of at least one low-privilege CephX key. Patches are available in Ceph 20.2.4 and 19.2.6, which add support for authenticated encryption using AES-256-HMAC-384 (RFC 8009).

Affected products

Ceph Ceph before 20.2.4 and 19.2.6

Timeline

2026-08-28: disclosed: CVE-2025-30156 published
2026: patched: Fixed in Ceph 20.2.4 and 19.2.6

References

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