CVE-2022-33684
Apache Pulsar C++/Python OAuth Clients prior to 3.0.0 were vulnerable to an MITM attack due to Disabled Certificate Validation
The Apache Pulsar C++ Client does not verify peer TLS certificates when making HTTPS calls for the OAuth2.0 Client Credential Flow, even when tlsAllowInsecureConnection is disabled via configuration. This vulnerability allows an attacker to perform a man in the middle attack and intercept and/or modify the GET request that is sent to the ClientCredentialFlow 'issuer url'. The intercepted credentials can be used to acquire authentication data from the OAuth2.0 server to then authenticate with an Apache Pulsar cluster. 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. The Apache Pulsar Python Client wraps the C++ client, so it is also vulnerable in the same way. This issue affects Apache Pulsar C++ Client and Python 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 to 2.10.1; 2.6.4 and earlier. Any users running affected versions of the C++ Client or the Python Client should rotate vulnerable OAuth2.0 credentials, including client_id and client_secret. 2.7 C++ and Python Client users should upgrade to 2.7.5 and rotate vulnerable OAuth2.0 credentials. 2.8 C++ and Python Client users should upgrade to 2.8.4 and rotate vulnerable OAuth2.0 credentials. 2.9 C++ and Python Client users should upgrade to 2.9.3 and rotate vulnerable OAuth2.0 credentials. 2.10 C++ and Python Client users should upgrade to 2.10.2 and rotate vulnerable OAuth2.0 credentials. 3.0 C++ users are unaffected and 3.0 Python Client users will be unaffected when it is released. Any users running the C++ and Python Client for 2.6 or less should upgrade to one of the above patched versions.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
The Apache Pulsar C++ Client does not verify peer TLS certificates when making HTTPS calls for the OAuth2.0 Client Credential Flow, even when tlsAllowInsecureConnection is disabled via configuration. This vulnerability allows an attacker to perform a man in the middle attack and intercept and/or modify the GET request that is sent to the ClientCredentialFlow 'issuer url'. The intercepted credentials can be used to acquire authentication data from the OAuth2.0 server to then authenticate with an Apache Pulsar cluster. 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. The Apache Pulsar Python Client wraps the C++ client, so it is also vulnerable in the same way. This issue affects Apache Pulsar C++ Client and Python 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 to 2.10.1; 2.6.4 and earlier. Any users running affected versions of the C++ Client or the Python Client should rotate vulnerable OAuth2.0 credentials, including client_id and client_secret. 2.7 C++ and Python Client users should upgrade to 2.7.5 and rotate vulnerable OAuth2.0 credentials. 2.8 C++ and Python Client users should upgrade to 2.8.4 and rotate vulnerable OAuth2.0 credentials. 2.9 C++ and Python Client users should upgrade to 2.9.3 and rotate vulnerable OAuth2.0 credentials. 2.10 C++ and Python Client users should upgrade to 2.10.2 and rotate vulnerable OAuth2.0 credentials. 3.0 C++ users are unaffected and 3.0 Python Client users will be unaffected when it is released. Any users running the C++ and Python Client for 2.6 or less should upgrade to one of the above patched versions.
- Record
CVE-2022-33684- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-295
- Updated
- 2026-11-02
CVE List
Apache Pulsar C++/Python OAuth Clients prior to 3.0.0 were vulnerable to an MITM attack due to Disabled Certificate Validation
The Apache Pulsar C++ Client does not verify peer TLS certificates when making HTTPS calls for the OAuth2.0 Client Credential Flow, even when tlsAllowInsecureConnection is disabled via configuration. This vulnerability allows an attacker to perform a man in the middle attack and intercept and/or modify the GET request that is sent to the ClientCredentialFlow 'issuer url'. The intercepted credentials can be used to acquire authentication data from the OAuth2.0 server to then authenticate with an Apache Pulsar cluster. 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. The Apache Pulsar Python Client wraps the C++ client, so it is also vulnerable in the same way. This issue affects Apache Pulsar C++ Client and Python 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 to 2.10.1; 2.6.4 and earlier. Any users running affected versions of the C++ Client or the Python Client should rotate vulnerable OAuth2.0 credentials, including client_id and client_secret. 2.7 C++ and Python Client users should upgrade to 2.7.5 and rotate vulnerable OAuth2.0 credentials. 2.8 C++ and Python Client users should upgrade to 2.8.4 and rotate vulnerable OAuth2.0 credentials. 2.9 C++ and Python Client users should upgrade to 2.9.3 and rotate vulnerable OAuth2.0 credentials. 2.10 C++ and Python Client users should upgrade to 2.10.2 and rotate vulnerable OAuth2.0 credentials. 3.0 C++ users are unaffected and 3.0 Python Client users will be unaffected when it is released. Any users running the C++ and Python Client for 2.6 or less should upgrade to one of the above patched versions.
- Record
CVE-2022-33684- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-295, CWE-295
- Updated
- 2026-11-02
EUVDEUVD-2022-7246
The Apache Pulsar C++ Client does not verify peer TLS certificates when making HTTPS calls for the OAuth2.0 Client Credential Flow, even when tlsAllowInsecureConnection is disabled via configuration. This vulnerability allows an attacker to perform a man in the middle attack and intercept and/or modify the GET request that is sent to the ClientCredentialFlow 'issuer url'. The intercepted credentials can be used to acquire authentication data from the OAuth2.0 server to then authenticate with an Apache Pulsar cluster. 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. The Apache Pulsar Python Client wraps the C++ client, so it is also vulnerable in the same way. This issue affects Apache Pulsar C++ Client and Python 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 to 2.10.1; 2.6.4 and earlier. Any users running affected versions of the C++ Client or the Python Client should rotate vulnerable OAuth2.0 credentials, including client_id and client_secret. 2.7 C++ and Python Client users should upgrade to 2.7.5 and rotate vulnerable OAuth2.0 credentials. 2.8 C++ and Python Client users should upgrade to 2.8.4 and rotate vulnerable OAuth2.0 credentials. 2.9 C++ and Python Client users should upgrade to 2.9.3 and rotate vulnerable OAuth2.0 credentials. 2.10 C++ and Python Client users should upgrade to 2.10.2 and rotate vulnerable OAuth2.0 credentials. 3.0 C++ users are unaffected and 3.0 Python Client users will be unaffected when it is released. Any users running the C++ and Python Client for 2.6 or less should upgrade to one of the above patched versions.
- Record
EUVD-2022-7246- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-5r3h-c3r7-9w4h
Apache Pulsar Disabled Certificate Validation for OAuth Client Credential Requests makes C++/Python Clients vulnerable to MITM attack
The Apache Pulsar C++ Client does not verify peer TLS certificates when making HTTPS calls for the OAuth2.0 Client Credential Flow, even when tlsAllowInsecureConnection is disabled via configuration. This vulnerability allows an attacker to perform a man in the middle attack and intercept and/or modify the GET request that is sent to the ClientCredentialFlow "issuer url". The intercepted credentials can be used to acquire authentication data from the OAuth2.0 server to then authenticate with an Apache Pulsar cluster. 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. The Apache Pulsar Python Client wraps the C++ client, so it is also vulnerable in the same way.
This issue affects Apache Pulsar C++ Client and Python 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 to 2.10.1; 2.6.4 and earlier.
Any users running affected versions of the C++ Client or the Python Client should rotate vulnerable OAuth2.0 credentials, including client_id and client_secret.
- 2.7 C++ and Python Client users should upgrade to 2.7.5 and rotate vulnerable OAuth2.0 credentials.
- 2.8 C++ and Python Client users should upgrade to 2.8.4 and rotate vulnerable OAuth2.0 credentials.
- 2.9 C++ and Python Client users should upgrade to 2.9.3 and rotate vulnerable OAuth2.0 credentials.
- 2.10 C++ and Python Client users should upgrade to 2.10.2 and rotate vulnerable OAuth2.0 credentials. 3.0 C++ users are unaffected and 3.0 Python Client users will be unaffected when it is released.
- Any users running the C++ and Python Client for 2.6 or less should upgrade to one of the above patched versions.
- Record
GHSA-5r3h-c3r7-9w4h- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-295
- Updated
- 2026-11-02
OSV
Apache Pulsar C++/Python OAuth Clients prior to 3.0.0 were vulnerable to an MITM attack due to Disabled Certificate Validation
The Apache Pulsar C++ Client does not verify peer TLS certificates when making HTTPS calls for the OAuth2.0 Client Credential Flow, even when tlsAllowInsecureConnection is disabled via configuration. This vulnerability allows an attacker to perform a man in the middle attack and intercept and/or modify the GET request that is sent to the ClientCredentialFlow 'issuer url'. The intercepted credentials can be used to acquire authentication data from the OAuth2.0 server to then authenticate with an Apache Pulsar cluster. 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. The Apache Pulsar Python Client wraps the C++ client, so it is also vulnerable in the same way. This issue affects Apache Pulsar C++ Client and Python 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 to 2.10.1; 2.6.4 and earlier. Any users running affected versions of the C++ Client or the Python Client should rotate vulnerable OAuth2.0 credentials, including client_id and client_secret. 2.7 C++ and Python Client users should upgrade to 2.7.5 and rotate vulnerable OAuth2.0 credentials. 2.8 C++ and Python Client users should upgrade to 2.8.4 and rotate vulnerable OAuth2.0 credentials. 2.9 C++ and Python Client users should upgrade to 2.9.3 and rotate vulnerable OAuth2.0 credentials. 2.10 C++ and Python Client users should upgrade to 2.10.2 and rotate vulnerable OAuth2.0 credentials. 3.0 C++ users are unaffected and 3.0 Python Client users will be unaffected when it is released. Any users running the C++ and Python Client for 2.6 or less should upgrade to one of the above patched versions.
- Record
CVE-2022-33684- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-295
- Updated
- 2026-11-02
OSVGHSA-5r3h-c3r7-9w4h
Apache Pulsar Disabled Certificate Validation for OAuth Client Credential Requests makes C++/Python Clients vulnerable to MITM attack
The Apache Pulsar C++ Client does not verify peer TLS certificates when making HTTPS calls for the OAuth2.0 Client Credential Flow, even when tlsAllowInsecureConnection is disabled via configuration. This vulnerability allows an attacker to perform a man in the middle attack and intercept and/or modify the GET request that is sent to the ClientCredentialFlow "issuer url". The intercepted credentials can be used to acquire authentication data from the OAuth2.0 server to then authenticate with an Apache Pulsar cluster. 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. The Apache Pulsar Python Client wraps the C++ client, so it is also vulnerable in the same way.
This issue affects Apache Pulsar C++ Client and Python 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 to 2.10.1; 2.6.4 and earlier.
Any users running affected versions of the C++ Client or the Python Client should rotate vulnerable OAuth2.0 credentials, including client_id and client_secret.
- 2.7 C++ and Python Client users should upgrade to 2.7.5 and rotate vulnerable OAuth2.0 credentials.
- 2.8 C++ and Python Client users should upgrade to 2.8.4 and rotate vulnerable OAuth2.0 credentials.
- 2.9 C++ and Python Client users should upgrade to 2.9.3 and rotate vulnerable OAuth2.0 credentials.
- 2.10 C++ and Python Client users should upgrade to 2.10.2 and rotate vulnerable OAuth2.0 credentials. 3.0 C++ users are unaffected and 3.0 Python Client users will be unaffected when it is released.
- Any users running the C++ and Python Client for 2.6 or less should upgrade to one of the above patched versions.
- Record
GHSA-5r3h-c3r7-9w4h- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-295
- Updated
- 2026-11-02
OSVPYSEC-2026-901
Apache Pulsar Disabled Certificate Validation for OAuth Client Credential Requests makes C++/Python Clients vulnerable to MITM attack
The Apache Pulsar C++ Client does not verify peer TLS certificates when making HTTPS calls for the OAuth2.0 Client Credential Flow, even when tlsAllowInsecureConnection is disabled via configuration. This vulnerability allows an attacker to perform a man in the middle attack and intercept and/or modify the GET request that is sent to the ClientCredentialFlow "issuer url". The intercepted credentials can be used to acquire authentication data from the OAuth2.0 server to then authenticate with an Apache Pulsar cluster. 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. The Apache Pulsar Python Client wraps the C++ client, so it is also vulnerable in the same way.
This issue affects Apache Pulsar C++ Client and Python 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 to 2.10.1; 2.6.4 and earlier.
Any users running affected versions of the C++ Client or the Python Client should rotate vulnerable OAuth2.0 credentials, including client_id and client_secret.
- 2.7 C++ and Python Client users should upgrade to 2.7.5 and rotate vulnerable OAuth2.0 credentials.
- 2.8 C++ and Python Client users should upgrade to 2.8.4 and rotate vulnerable OAuth2.0 credentials.
- 2.9 C++ and Python Client users should upgrade to 2.9.3 and rotate vulnerable OAuth2.0 credentials.
- 2.10 C++ and Python Client users should upgrade to 2.10.2 and rotate vulnerable OAuth2.0 credentials. 3.0 C++ users are unaffected and 3.0 Python Client users will be unaffected when it is released.
- Any users running the C++ and Python Client for 2.6 or less should upgrade to one of the above patched versions.
- Record
PYSEC-2026-901- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
pulsar-clientPyPI |
before 2.7.5 | 2.7.5 |
pulsar-clientPyPI |
2.8.0 up to 2.8.4 | 2.8.4 |
pulsar-clientPyPI |
2.9.0 up to 2.9.3 | 2.9.3 |
pulsar-clientPyPI |
2.10.0 up to 2.10.2 | 2.10.2 |
pulsar-clientPyPI |
before 2.7.5, plus listed versions 1.18.dev11.19.01.19.dev11.19.dev21.20.0 Show 29 moreShow less1.21.01.22.02.0.02.0.12.1.02.1.12.2.02.2.12.3.02.3.0.post12.3.12.3.22.4.02.4.12.4.1.post12.4.22.5.02.5.12.5.22.6.02.6.12.6.22.6.32.7.02.7.12.7.22.7.2.post02.7.32.7.4 |
2.7.5 |
pulsar-clientPyPI |
2.8.0 up to 2.8.4, plus listed versions 2.8.0.post02.8.12.8.22.8.3 |
2.8.4 |
pulsar-clientPyPI |
2.9.0 up to 2.9.3, plus listed versions 2.9.12.9.2 |
2.9.3 |
pulsar-clientPyPI |
2.10.0 up to 2.10.2, plus listed versions 2.10.1 |
2.10.2 |
pulsar-clientPyPI |
before 2.7.5, 2.8.0 up to 2.8.4, 2.9.0 up to 2.9.3, 2.10.0 up to 2.10.2, plus listed versions 1.18.dev11.19.01.19.dev11.19.dev21.20.0 Show 36 moreShow less1.21.01.22.02.0.02.0.12.1.02.1.12.10.12.2.02.2.12.3.02.3.0.post12.3.12.3.22.4.02.4.12.4.1.post12.4.22.5.02.5.12.5.22.6.02.6.12.6.22.6.32.7.02.7.12.7.22.7.2.post02.7.32.7.42.8.0.post02.8.12.8.22.8.32.9.12.9.2 |
2.7.52.8.42.9.32.10.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2022-33684 is a high vulnerability (CVSS 8.1) in Apache Pulsar, published November 4, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.93%, the 60th percentile. Fixed in pulsar-client 2.7.5.
References
lists.apache.org/thread/ky1ssskvkj00y36k7nys9b5gm5jjrzwv
huntr.dev/bounties/df89b724-3201-47aa-b8cd-282e112a566f
nvd.nist.gov/vuln/detail/CVE-2022-33684
github.com/apache/pulsar/pull/16064
pypi.org/project/pulsar-client