Data leakage and state poisoning via hash collisions
Published Jun 22, 2026 · Updated Jun 22, 2026
Cache poisoning in Angular 19.2.25 and earlier and before 20.3.25, 21.2.17, and 22.0.1 allows remote attackers to alter SSR state. HttpTransferCache hashes request properties into a 32-bit DJB2-like key, so attacker-chosen collisions overwrite another response in TransferState. Applications are exposed only when SSR hydration uses transfer caching; the poisoned response results in sensitive-data exposure or forged client state.
Summary
What happened
Cache poisoning in Angular 19.2.25 and earlier and before 20.3.25, 21.2.17, and 22.0.1 allows remote attackers to alter SSR state. HttpTransferCache hashes request properties into a 32-bit DJB2-like key, so attacker-chosen collisions overwrite another response in TransferState. Applications are exposed only when SSR hydration uses transfer caching; the poisoned response results in sensitive-data exposure or forged client state.
The record
- CVE
- CVE-2026-54266
- Published
- Jun 22, 2026
- Updated
- Jun 22, 2026
- Vendor
- Go standard library
- Product
- Angular
- Classifications
- CWE-328, CWE-345, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 22, 2026CVE publishedPublication date reported by the CVE source.
- Jun 22, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=<= 19.2.25
- Affected versionversion=>= 20.0.0-next.0 < 20.3.25
- Affected versionversion=>= 21.0.0-next.0 < 21.2.17
- Affected versionversion=>= 22.0.0-next.0 < 22.0.1
What conditions does exploitation require?
What is affected?
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.
Weakness, pattern, technique
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
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo