8.1

CVE-2022-33684: apache software foundation apache pulsar Improper Certificate Validation

CVSS: 8.1v3.1HighModified
AliasesGHSA-5r3h-c3r7-9w4hPYSEC-2026-901
Published 04-11-2022Last modified 02-05-2025
Open JSON

Vulnerability summary

CVE-2022-33684 is a high (CVSS 8.1) Improper Certificate Validation vulnerability in apache software foundation apache pulsar. EPSS estimates a 0.78% chance of exploitation in the next 30 days, higher than 54.9% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
43/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.78%
0%100%
Low · +0.03 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference

Timeline

  1. 04-11-2022
    PublishedVulnerability first disclosed.
  2. 02-05-2025
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.78%

Chance of exploitation in the next 30 days

Percentile

55%

Versus all other CVEs

30-day change

+0.03 pp

From 0.74% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.78%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (huntr.dev)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Apache1 product
  • pulsar≤ 2.6.4 | ≥ 2.7.0, < 2.7.5 | ≥ 2.8.0, < 2.8.4 | ≥ 2.9.0, < 2.9.3 | ≥ 2.10.0, < 2.10.2
Apache software foundation1 product
  • apache pulsar≥ 2.7, ≤ 2.7.4 | ≥ 2.8, ≤ 2.8.3 | ≥ 2.9, ≤ 2.9.2 | ≥ 2.10, ≤ 2.10.1 | ≥ 2.6 and earlier, ≤ 2.6.4
PyPI1 product
  • pulsar-client< 2.7.5 | ≥ 2.8.0, < 2.8.4 | ≥ 2.9.0, < 2.9.3 | ≥ 2.10.0, < 2.10.2

3 vendors · 3 products

References

7 links