SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2025-36852

A critical security vulnerability exists in remote cache extensions for common build systems utilizing bucket-based remote cache (such as those using Amazon S3, Google Cloud Storage, or similar object storage) that allows any contributor with pull…

CRITICAL 9.4EPSS 0.24%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.24%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A critical security vulnerability exists in remote cache extensions for common build systems utilizing bucket-based remote cache (such as those using Amazon S3, Google Cloud Storage, or similar object storage) that allows any contributor with pull request privileges to inject compromised artifacts from an untrusted environment into trusted production environments without detection.  The vulnerability exploits a fundamental design flaw in the "first-to-cache wins" principle, where artifacts built in untrusted environments (feature branches, pull requests) can poison the cache used by trusted environments (protected branches, production deployments).  This attack bypasses all traditional security measures including encryption, access controls, and checksum validation because the poisoning occurs during the artifact construction phase, before any security measures are applied.

CVSS 4.0
9.4 CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.24% probability · 15th percentile
CISA KEV
Not listed
Weakness
CWE-829
Source
36c7be3b-2937-45df-85ea-ca7133ea542c

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.