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Fencer Vulns
high 7.4

CVE-2023-51437 json

Apache Pulsar: Timing attack in SASL token signature verification

published 2024-02-07 2 y ago modified 2026-06-17 4 mo ago also GHSA-c57v-4vg5-cm2x , EUVD-2024-0609

cvss
7.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.8%
EPSS 0.8% chance of exploitation in 30 days, percentile 55%
public exploits
0
none known

Summary

Observable timing discrepancy vulnerability in Apache Pulsar SASL Authentication Provider can allow an attacker to forge a SASL Role Token that will pass signature verification. Users are recommended to upgrade to version 2.11.3, 3.0.2, or 3.1.1 which fixes the issue. Users should also consider updating the configured secret in the `saslJaasServerRoleTokenSignerSecretPath` file.

Any component matching an above version running the SASL Authentication Provider is affected. That includes the Pulsar Broker, Proxy, Websocket Proxy, or Function Worker.

2.11 Pulsar users should upgrade to at least 2.11.3. 3.0 Pulsar users should upgrade to at least 3.0.2. 3.1 Pulsar users should upgrade to at least 3.1.1. Any users running Pulsar 2.8, 2.9, 2.10, and earlier should upgrade to one of the above patched versions.

For additional details on this attack vector, please refer to https://codahale.com/a-lesson-in-timing-attacks/ .

Patch / fix

  • maven org.apache.pulsar:pulsar-broker-auth-sasl 2.11.3, 3.0.2, 3.1.1
  • apache pulsar 2.11.3, 3.0.2

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

0.76% chance of exploitation in the next 30 days, higher than 55% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
NVD 3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
GitHub 3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Affected packages

ecosystem package affected fixed in
maven org.apache.pulsar:pulsar-broker-auth-sasl
<2.11.3
>=3.0.0, <3.0.2
>=3.1.0, <3.1.1
2.11.3
3.0.2
3.1.1

Affected products

  • Apache Software Foundation Apache Pulsar

Classification

Weakness
  • CWE-203 Observable Discrepancy
  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

References

Sources

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