CVE-2022-33681Improper Hostname Verification in Java Client and Proxy can expose authentication data via MITM
- 5.9MediumCVSS base score
- 0.70%Exploitation in 30 daysEPSS · top 46% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Delayed TLS hostname verification in the Pulsar Java Client and the Pulsar Proxy make each client vulnerable to a man in the middle attack. Connections from the Pulsar Java Client to the Pulsar Broker/Proxy and connections from the Pulsar Proxy to the Pulsar Broker are vulnerable. Authentication data is sent before verifying the server’s TLS certificate matches the hostname, which means authentication data could be exposed to an attacker. An attacker can only take advantage of this vulnerability by taking control of a machine 'between' the client and the server. The attacker must then actively manipulate traffic to perform the attack by providing the client with a cryptographically valid certificate for an unrelated host. Because the client sends authentication data before performing hostname verification, an attacker could gain access to the client’s authentication data. The client eventually closes the connection when it verifies the hostname and identifies the targeted hostname does not match a hostname on the certificate. Because the client eventually closes the connection, the value of the intercepted authentication data depends on the authentication method used by the client. Token based authentication and username/password authentication methods are vulnerable because the authentication data can be used to impersonate the client in a separate session. This issue affects Apache Pulsar Java Client versions 2.7.0 to 2.7.4; 2.8.0 to 2.8.3; 2.9.0 to 2.9.2; 2.10.0; 2.6.4 and earlier.
Timeline
ID reserved
By apache
- 3 months later
· 3 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N |
| NVDNVD · Modified | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.70% · top 46% of all CVEs (15 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.9.
Affected products
Apache Software Foundation · Apache Pulsar
- affected 2.10.0
- affected 2.7 – ≤ 2.7.4
- affected 2.8 – ≤ 2.8.3
- affected 2.9 – ≤ 2.9.2
- affected 2.6 and earlier – ≤ 2.6.4
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Mavenorg.apache.pulsar:pulsar-clientGHSA-c5fp-x2h5-vjv7 (opens in a new tab)
What to do
Workaround: Any users running affected versions of the Java Client should rotate vulnerable authentication data, including tokens and passwords. 2.7 Pulsar Java Client users should upgrade to 2.7.5, and rotate vulnerable authentication data, including tokens and passwords. 2.8 Pulsar Java Client users should upgrade to 2.8.4, and rotate vulnerable authentication data, including tokens and passwords. 2.9 Pulsar Java Client users should upgrade to 2.9.3, and rotate vulnerable authentication data, including tokens and passwords. 2.10 Pulsar Java Client users should upgrade to 2.10.1, and rotate vulnerable authentication data, including tokens and passwords. Any users running the Pulsar Java Client for 2.6.4 and earlier should upgrade to one of the above patched versions, and rotate vulnerable authentication data, including tokens and passwords.
References
References1
- https://lists.apache.org/thread/fpo6x10trvn20hlk0dmnr5vlz5v4kl3d (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2022-6774 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-c5fp-x2h5-vjv7 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2022-33681)Record last updated .