CVE-2026-48034

highpriority · track · 0EPSS 0.004 · 39 %ileEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.45% (39th) EPSS
CVSS 8.5 · high
Is it mine?
2 products
Check your exposure
Who says so?
3 sources
cnnvd · enisa_euvd · osv

EPSS · scored 2026-10-27

Hulumi is an open-source toolkit that ships secure-by-default cloud and platform infrastructure components for Pulumi. Prior to version 1.4.0, there is a bypass via decoy sibling resources targeting a different bucket. This issue has been patched in version 1.4.0.

01

cvss

Technical severity, 0–10. One row per scoring source.

8.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.8–8.5

v4.08.5highCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:Lsecondary · ENISA EU
v4.08.5highCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:L/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:Xsecondary · security-advisories@github.com
v4.05.8mediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:L/E:U/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:Xsecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

04

affected products (2)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • GHSA-9vc9-4jv3-rf86@hulumi/policies has a HULUMI-H5 bypass via decoy sibling resources targeting a different bucket2026-06-10ghsa · osvUS

    **Affected:** `@hulumi/policies` `< 1.4.0` — **Fixed in:** `1.4.0` — **Severity:** High — **CWE-284 (Improper Access Control)** #### Summary HULUMI-H1 forbids raw `aws:s3:Bucket` outside of Hulumi's `SecureBucket` component, with one exemption: a raw bucket that's a child of a `SecureBucket` is allowed because the component is responsible for the hardening. HULUMI-H5 is the defence-in-depth check that closes the H1 exemption — for any raw bucket claiming it, H5 verifies the five hardening sibling resources a real `SecureBucket` always emits (public-access block, SSE-KMS, ownership controls, versioning, TLS-only bucket policy) are actually present. The bug: H5 only checked the siblings' _types_. It never verified that those siblings actually applied to the bucket being exempted. A consumer (or compromised PR) could pair an unhardened raw bucket with five hardening sibling resources whose `bucket` property pointed at a _completely different_ bucket, and H5 would report no violation while the actual bucket shipped with zero hardened defaults. #### Impact Consumers using `HulumiHardeningPack` could ship a raw S3 bucket with no public-access block, no SSE-KMS, no ownership controls, no versioning, and no TLS-only bucket policy — while the policy pack reported the stack as compliant. #### Patches Upgrade to `@hulumi/policies@1.4.0`. The H5 sibling check now requires both (a) the sibling to share the same parent `SecureBucket` instance via the anchored URN helper from GHSA-2, AND (b) the sibling's `bucket` property — or, for the bucket policy, its `Resource` ARN list — to reference the exempted bucket explicitly. Five decoy siblings pointing at a different bucket no longer count. #### Workarounds None — the exemption itself is the mechanism, so the value-binding check is the only fix. #### Resources - [PR #178](https://github.com/kerberosmansour/hulumi/pull/178) (Cluster B); decoy-sibling regression cases in `packages/policies/tests/hulumi-hardening-pack.test.ts`. Supersedes [PR #175](https://github.com/kerberosmansour/hulumi/pull/175), which had addressed the value-binding half but on a stale base.

06

also known as (3)

Other names and identifiers for this entity.

07

sources

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published 2026-07-24modified 2026-10-24
08

references (12)

External citations — patches, advisories, analysis.

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