CVE-2026-126570: Padloc prototype pollution in SCIM (high)

Q: Is CVE-2026-126570 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Q: What does this mean?

A flaw in how SCIM PATCH requests are processed lets a request modify Object.prototype in the shared server process. This can cause request failures and disruption for other organizations handled by the same server.

Q: Which versions are affected by CVE-2026-126570?

padloc: from 4.0.0 before 4.3.1.

Q: Am I affected, and how do I check?

Padloc server versions 4.0.0 up to but not including 4.3.1 are affected, with 4.3.0 confirmed affected, and SCIM must be enabled on the server. To check, look at the server version and whether SCIM is enabled in its configuration.

Q: How do I fix CVE-2026-126570?

Upgrade the server to 4.3.1 or later.

Summary

Padloc 4.0.0 before 4.3.1 is affected by a prototype pollution flaw in its SCIM user-patch handling. Remotely, an attacker holding a SCIM token can pollute the shared server process and disrupt requests for other organizations.

Read the original description

Padloc 4.0.0 before 4.3.1 contains a prototype pollution vulnerability that allows SCIM token holders to modify Object.prototype by sending crafted SCIM PATCH paths to ScimServer._handleScimUsersPatch(). Attackers can supply paths like __proto__.x or constructor.prototype.x passed to setPath() to pollute the shared server process, disrupting requests for all other organizations.

Who should check

Teams running the Padloc @padloc/server (4.0.0 to before 4.3.1) with SCIM user provisioning enabled, including self-hosted and Docker deployments

Read the source excerpt

“Affecting padloc >= 4.0.0, < 4.3.1”

vulncheck.com

cve.now Index

15Pcve.now Index 15 of 100 · methodology v3 · provisional

Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
Exposure8/25Specific setups only, reachable over the network
Reach?/20Unknown. No tracked technology or package matched
Severity7/10CVSS 7.0
No patch0/5No signal

What would change the score

Would score about 65 if added to CISA KEV
Would score about 60 if CISA's SSVC rates exploitation active
Would score about 22 if CISA's SSVC rates it automatable

How the score works · Rankings

What to do

Check whether your setup matches what the bug needs.
Padloc server version 4.0.0 up to but not including 4.3.1 (confirmed affected release: 4.3.0) SCIM must be enabled on the server
Upgrade to a fixed version: 4.3.1.

Check your systems with an agent

Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.

Check whether my systems are affected by CVE-2026-126570 (Padloc 4.0.0 before 4.3.1 Prototype Pollution via SCIM PATCH setPath()), using the cve.now data below.

Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.

What cve.now has for CVE-2026-126570 (entry last updated 2026-11-11):
Affected:
- padloc padloc: from 4.0.0, fixed in 4.3.1
Fixed versions: 4.3.1.
Conditions (all must be true for the bug to be hit):
- Padloc server version 4.0.0 up to but not including 4.3.1 (confirmed affected release: 4.3.0) (source: https://www.vulncheck.com/advisories/padloc-4.0.0-before-4.3.1-prototype-pollution-via-scim-patch-setpath)
- SCIM must be enabled on the server (source: https://github.com/padloc/padloc/security/advisories/GHSA-crhv-mjrg-8vwm)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: network access, high-privilege login, no user action.
CISA KEV: CVE-2026-126570 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-126570 only. If you also check another CVE, look up its own KEV status; never assume it from this one.

How to check:
- Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory.

Verify against the linked advisories before concluding, and cite the date you read each one:
- https://github.com/padloc/padloc/security/advisories/GHSA-crhv-mjrg-8vwm
- https://github.com/padloc/padloc/commit/7dd3d230ef299c71ac215c802600b5f2358f7ba3
- https://github.com/padloc/padloc/blob/v4.3.0/packages/server/src/scim.ts#L421-L428
- https://github.com/padloc/padloc/blob/v4.3.0/packages/core/src/util.ts#L239-L251
- https://www.vulncheck.com/advisories/padloc-4.0.0-before-4.3.1-prototype-pollution-via-scim-patch-setpath
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.

Entry: https://cve.now/CVE-2026-126570
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example get_vulnerability with id CVE-2026-126570.

Timeline

Nov 11, 2026, 2:36 AM UTCCVE published
Nov 11, 2026, 2:40 AM UTCFirst seen by cve.now

Affected versions

padloc padloc
From 4.0.0 · fixed in 4.3.1

Evidence 7

Vendor advisory · 1

Establishes: Affected and fixed versions.

Advisory
GitHub · padloc/padloc · Advisory GHSA-crhv-mjrg-8vwm

CVE record · 2

Establishes: The identifier and description.

Record
CVE List · CVE-2026-126570
Record
NVD · CVE-2026-126570

Corrections

None so far.

Something wrong on this page? Report an error. Every fix is listed here.

Questions about CVE-2026-126570

Is CVE-2026-126570 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data

What does this mean?

A flaw in how SCIM PATCH requests are processed lets a request modify Object.prototype in the shared server process. This can cause request failures and disruption for other organizations handled by the same server.Source: vulncheck.com, github.com

Which versions are affected by CVE-2026-126570?

padloc: from 4.0.0 before 4.3.1.Source: cve.now feed data

Am I affected, and how do I check?

Padloc server versions 4.0.0 up to but not including 4.3.1 are affected, with 4.3.0 confirmed affected, and SCIM must be enabled on the server. To check, look at the server version and whether SCIM is enabled in its configuration.Source: vulncheck.com, github.com

How do I fix CVE-2026-126570?

Upgrade the server to 4.3.1 or later.Source: vulncheck.com, github.com

Padloc 4.0.0 before 4.3.1 Prototype Pollution via SCIM PATCH setPath()