# CVE-2026-54266: Angular: Weak 32-Bit Cache Key Hashing in `HttpTransferCache` Leading to Cross-Request Data Leakage and State Poisoning

> Attackers can exploit weak hashing in Angular's SSR cache to cause collisions, leaking sensitive data or poisoning state via crafted links.

- **Severity:** High 8.8 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 22 Jun 2026
- **Updated:** 22 Jun 2026
- **Also known as:** DEBIAN-CVE-2026-54266, GHSA-39pv-4j6c-2g6v, UBUNTU-CVE-2026-54266

## What is CVE-2026-54266?

CVE-2026-54266 is a high-severity vulnerability in angular, published on 22 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Prior to 22.0.1, 21.2.17, and 20.3.25, Angular's HttpTransferCache caches HTTP requests made during Server-Side Rendering (SSR) so that they can be reused during client-side hydration. This avoids repeating the same HTTP requests on the client. The cached responses are stored in TransferState using a cache key generated by hashing request properties (method, response type, mapped URL, serialized body, and sorted query parameters). The cache keys are generated using a weak 32-bit DJB2-like polynomial rolling hash. The 32-bit hash space is extremely small, allowing attackers to find hash collisions. An attacker can easily find a query parameter string (e.g., q=aaCAZMMM for a search request) that produces the exact same 32-bit hash as a sensitive endpoint (e.g., /api/user/profile). When a victim visits a crafted link containing the colliding parameter, the SSR process executes both the search request and the profile request. Due to the hash collision, the search response overwrites the profile response in the TransferState cache. This vulnerability is fixed in 22.0.1, 21.2.17, and 20.3.25.

Weakness: CWE-345 (Insufficient Verification of Data Authenticity), CWE-328 (Use of Weak Hash)

## Which versions are affected by CVE-2026-54266?

8 open source packages ship an affected version, including @angular/common. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@angular/common` | npm | All versions to 19.2.25 | None |
| `@angular/common` | npm | All versions to 19.2.25 | None |
| `@angular/common` | npm | From 20.0.0-next.0 | 20.3.25 |
| `@angular/common` | npm | From 20.0.0-next.0 | 20.3.25 |
| `@angular/common` | npm | From 21.0.0-next.0 | 21.2.17 |
| `@angular/common` | npm | From 21.0.0-next.0 | 21.2.17 |
| `@angular/common` | npm | From 22.0.0-next.0 | 22.0.1 |
| `@angular/common` | npm | From 22.0.0-next.0 | 22.0.1 |

Products: Angular Angular.

## How do I fix CVE-2026-54266?

Upgrade @angular/common to a fixed version for your release line: 20.3.25, 21.2.17 or 22.0.1.

## Is CVE-2026-54266 being exploited?

There is no known exploitation of CVE-2026-54266 in the wild and no public exploit code.

## Other vulnerabilities in angular

- [CVE-2026-68945](https://insights.sbomify.com/CVE-2026-68945/): Angular: Cache-Key Ambiguity in HttpTransferCache Leading to Cross-Request Response Reuse and State Poisoning (high 8.8)
- [CVE-2026-46417](https://insights.sbomify.com/CVE-2026-46417/): Angular: SSRF via Hostname Hijacking in @angular/platform-server (high 8.8)
- [CVE-2026-50168](https://insights.sbomify.com/CVE-2026-50168/): Angular: URL Parser Differential in @angular/platform-server leading to SSRF Allowlist Bypass (high 8.8)
- [CVE-2026-41423](https://insights.sbomify.com/CVE-2026-41423/): Angular: SSRF via protocol-relative and backslash URLs in Angular Platform-Server (high 8.7)
- [CVE-2026-88056](https://insights.sbomify.com/CVE-2026-88056/): Angular: SSRF and Cross-Origin Credential Disclosure via URL Resolution Discrepancy in SSR (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-54266 and fix it if it is affected.

What it is: CVE-2026-54266 is a high-severity vulnerability in angular, published on 22 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-54266 in the wild and no public exploit code.

Affected packages and fixed versions:
- @angular/common (npm): affected all versions up to 19.2.25; no fix listed
- @angular/common (npm): affected all versions up to 19.2.25; no fix listed
- @angular/common (npm): affected from 20.0.0-next.0; fixed in 20.3.25
- @angular/common (npm): affected from 20.0.0-next.0; fixed in 20.3.25
- @angular/common (npm): affected from 21.0.0-next.0; fixed in 21.2.17
- @angular/common (npm): affected from 21.0.0-next.0; fixed in 21.2.17
- @angular/common (npm): affected from 22.0.0-next.0; fixed in 22.0.1
- @angular/common (npm): affected from 22.0.0-next.0; fixed in 22.0.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-54266/ (Markdown: https://insights.sbomify.com/CVE-2026-54266/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-54266
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-54266
- OSV: https://osv.dev/vulnerability/CVE-2026-54266

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-54266/
Summaries are generated and may contain mistakes; the official description above is the record.