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CVE-2025-59052NVD status: Deferred

angular: Concurrent Execution using Shared Resource with Improper Synchronization

CVE-2025-59052 is a high-severity concurrent execution using shared resource with improper synchronization vulnerability in angular, with a CVSS 4.0 base score of 7.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected angular versions: @angular/platform-server >= 16.0.0-next.0, < 18.2.14; @angular/platform-server >= 20.0.0-next.0, < 20.3.0; @angular/platform-server >= 19.0.0-next.0, < 19.2.15, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.37% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of angular you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  4. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
Angularangular@angular/platform-server >= 16.0.0-next.0, < 18.2.14; @angular/platform-server >= 20.0.0-next.0, < 20.3.0; @angular/platform-server >= 19.0.0-next.0, < 19.2.15; @angular/platform-server >= 21.0.0-next.0, < 21.0.0-next.3; @angular/ssr >= 17.0.0-next.0, < 18.2.21; @angular/ssr >= 19.0.0-next.0, < 19.2.16; @angular/ssr >= 20.0.0-next.0, < 20.3.0; @angular/ssr >= 21.0.0-next.0, < 21.0.0-next.3; and 1 more rangesNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Attack requirements
NoneThe attack does not depend on a particular deployment or configuration.
Privileges required
NoneNo account or login is needed.
User interaction
PassiveA user only needs to do something routine, such as viewing a page.
Confidentiality (vulnerable system)
HighSerious loss of confidentiality on the vulnerable system.
Integrity (vulnerable system)
LowLimited loss of integrity on the vulnerable system.
Availability (vulnerable system)
NoneNo loss of availability on the vulnerable system.
Confidentiality (other systems)
NoneNo loss of confidentiality on systems beyond the vulnerable one.
Integrity (other systems)
NoneNo loss of integrity on systems beyond the vulnerable one.
Availability (other systems)
NoneNo loss of availability on systems beyond the vulnerable one.

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (github.com).

Official description

Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Angular uses a DI container (the "platform injector") to hold request-specific state during server-side rendering. For historical reasons, the container was stored as a JavaScript module-scoped global variable. When multiple requests are processed concurrently, they could inadvertently share or overwrite the global injector state. In practical terms, this can lead to one request responding with data meant for a completely different request, leaking data or tokens included on the rendered page or in response headers. As long as an attacker had network access to send any traffic that received a rendered response, they may have been able to send a large number of requests and then inspect the responses for information leaks. The APIs `bootstrapApplication`, `getPlatform`, and `destroyPlatform` were vulnerable and required SSR-only breaking changes. The issue has been patched in all active release lines as well as in the v21 prerelease. Patched packages include `@angular/platform-server` 21.0.0-next.3, 20.3.0, 19.2.15, and 18.2.14 and `@angular/ssr` 21.0.0-next.3, 20.3.0, 19.2.16, and 18.2.21. Several workarounds are available. Disable SSR via Server Routes or builder options, remove any asynchronous behavior from custom `bootstrap` functions, remove uses of `getPlatform()` in application code, and/or ensure that the server build defines `ngJitMode` as false.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Concurrent Execution using Shared Resource with Improper Synchronization

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

How developers prevent this class of flaw

  • In languages that support it, use synchronization primitives. Only wrap these around critical code to minimize the impact on performance.
  • Use thread-safe capabilities such as the data access abstraction in Spring.
  • Minimize the usage of shared resources in order to remove as much complexity as possible from the control flow and to reduce the likelihood of unexpected conditions occurring. Additionally, this will minimize the amount of synchronization necessary and may even help to reduce the likelihood of a denial of service where an attacker may be able to repeatedly trigger a critical section (CWE-400).

More Concurrent Execution using Shared Resource with Improper Synchronization vulnerabilities (CWE-362)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in angular

All angular vulnerabilities

Recent Concurrent Execution using Shared Resource with Improper Synchronization vulnerabilities

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