CVE-2026-59304Network attack vector

Data exposure and alteration via stale content-type cache

Published Aug 27, 2026 · Updated Aug 27, 2026

Improper caching in Spring Cloud Stream Avro allows remote authenticated users to expose or alter data through crafted message processing. Spring identifies the original content-type cache as the affected locus but has not published the exact stale-value operation or cache implementation. Reachability requires Avro message conversion, high privileges, and user interaction; reported impact is limited to confidentiality and integrity.

CVSS severity3.1
Low
EPSS probability0.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper caching in Spring Cloud Stream Avro allows remote authenticated users to expose or alter data through crafted message processing. Spring identifies the original content-type cache as the affected locus but has not published the exact stale-value operation or cache implementation. Reachability requires Avro message conversion, high privileges, and user interaction; reported impact is limited to confidentiality and integrity.

The record

CVE
CVE-2026-59304
Published
Aug 27, 2026
Updated
Aug 27, 2026
Vendor
Spring
Product
Spring Cloud Stream
Classifications
Unavailable
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.2.0 <=4.2.6
  2. Affected versionversion=4.3.0 <=4.3.3
  3. Affected versionversion=5.0.0 <=5.0.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Spring · Spring Cloud Streamversion=4.2.0 <=4.2.6; version=4.3.0 <=4.3.3; version=5.0.0 <=5.0.2

Published CVSS scores

3.1SpringCVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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