Linux Distros Unpatched Vulnerability : CVE-2026-82417

medium Nessus Plugin ID 341603

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- ### Summary `qs.stringify` throws a `TypeError` when it serializes an object whose own `constructor` property has a truthy, non-callable `isBuffer` member. `utils.isBuffer` duck-types buffers by calling `obj.constructor.isBuffer(obj)` after checking only that the property is truthy, so a value such as `{ constructor: { isBuffer: x } }` makes the call throw `TypeError: obj.constructor.isBuffer is not a function`. ### Details `lib/stringify.js:127` calls `utils.isBuffer` on every non-primitive value it serializes. `utils.isBuffer` (`lib/utils.js:332`) reads `obj.constructor.isBuffer` and invokes it without verifying that it is a function. `constructor` and `isBuffer` are ordinary property names, so any object carrying them as own properties reaches the unchecked call. Such an object can be built from untrusted input. `qs.parse(x[constructor][isBuffer]=y, { plainObjects: true })` or `{ allowPrototypes: true }` keeps the `constructor` key as an own property (the default parse options drop it), and `JSON.parse({\a\:{\constructor\:{\isBuffer\:\x\}}})` produces the same shape with no qs option involved. Express 4 with its default `query parser` setting and body-parser with `extended: true` both call `qs.parse` with `allowPrototypes: true`, so on those stacks `req.query` and `req.body` can carry the shape directly. #### PoC ```js var qs = require(qs); qs.stringify(qs.parse(x[constructor][isBuffer]=y, { plainObjects: true })); qs.stringify(JSON.parse({\a\:{\constructor\:{\isBuffer\:\x\}}})); // TypeError: obj.constructor.isBuffer is not a function // at Object.isBuffer (lib/utils.js:332:78) // at stringify (lib/stringify.js:127:45) ``` #### Fix `lib/utils.js`, applied in e83d321 on `main` and released as v6.16.0: ```diff - return !!(obj.constructor && obj.constructor.isBuffer && obj.constructor.isBuffer(obj)); + return !!(obj.constructor && typeof obj.constructor.isBuffer === function && obj.constructor.isBuffer(obj)); ``` Real `Buffer`, `safer-buffer`, and browserify `buffer` polyfill instances serialize exactly as before; only the throw is removed. ### Affected versions `>=2.2.5 <6.16.0`, fixed in v6.16.0. The unguarded duck-type was introduced in 3768a75 and first shipped in v2.2.5 (September 2014). v2.2.4 and earlier used `Buffer.isBuffer` and are not affected. Every release from v2.2.5 through v6.15.3 contains the unguarded call. ### Impact An unauthenticated request can make any code path that re-serializes attacker-influenced data with `qs.stringify` (for example, rebuilding a query string from `req.query` for a redirect or an upstream request, or serializing a parsed JSON body) throw synchronously. In a typical Node.js HTTP framework the throw is caught by the framework error boundary and the affected request returns a 500; the process survives and other requests are unaffected. Where the call runs outside an error boundary, such as an `async` Express 4 handler (where the throw becomes an unhandled promise rejection) or a background job, the process exits, so the impact in that case depends on the application error handling rather than on qs. (CVE-2026-82417)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://access.redhat.com/security/cve/cve-2026-82417

https://security-tracker.debian.org/tracker/CVE-2026-82417

https://ubuntu.com/security/CVE-2026-82417

Plugin Details

Severity: Medium

ID: 341603

File Name: unpatched_CVE_2026_82417.nasl

Version: 1.12

Type: Local

Agent: unix

Family: Misc.

Published: 8/30/2026

Updated: 9/17/2026

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 1.2

Percentile: 0.01

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 4.3

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2026-82417

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.9

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

CVSS v4

Risk Factor: Medium

Base Score: 6.3

Threat Score: 1.7

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:14.04:-:lts, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, cpe:/o:canonical:ubuntu_linux:26.04:-:lts, cpe:/o:centos:centos:7, cpe:/o:centos:centos:8, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, cpe:/o:redhat:enterprise_linux:10, cpe:/o:redhat:enterprise_linux:7, cpe:/o:redhat:enterprise_linux:8, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:canonical:ubuntu_linux:node-qs, p-cpe:/a:centos:centos:grafana-azure-monitor, p-cpe:/a:centos:centos:grafana-cloudwatch, p-cpe:/a:centos:centos:grafana-elasticsearch, p-cpe:/a:centos:centos:grafana-graphite, p-cpe:/a:centos:centos:grafana-influxdb, p-cpe:/a:centos:centos:grafana-loki, p-cpe:/a:centos:centos:grafana-mssql, p-cpe:/a:centos:centos:grafana-mysql, p-cpe:/a:centos:centos:grafana-opentsdb, p-cpe:/a:centos:centos:grafana-pcp, p-cpe:/a:centos:centos:grafana-postgres, p-cpe:/a:centos:centos:grafana-prometheus, p-cpe:/a:centos:centos:grafana-selinux, p-cpe:/a:centos:centos:grafana-stackdriver, p-cpe:/a:centos:centos:grafana, p-cpe:/a:centos:centos:librados-devel, p-cpe:/a:centos:centos:librados2, p-cpe:/a:centos:centos:libradospp-devel, p-cpe:/a:centos:centos:librbd-devel, p-cpe:/a:centos:centos:librbd1, p-cpe:/a:centos:centos:linux-sgx, p-cpe:/a:centos:centos:mozjs60-devel, p-cpe:/a:centos:centos:mozjs60, p-cpe:/a:centos:centos:nodejs-devel, p-cpe:/a:centos:centos:nodejs-docs, p-cpe:/a:centos:centos:nodejs-full-i18n, p-cpe:/a:centos:centos:nodejs-libs, p-cpe:/a:centos:centos:nodejs-npm, p-cpe:/a:centos:centos:nodejs22, p-cpe:/a:centos:centos:nodejs24-devel, p-cpe:/a:centos:centos:nodejs24-docs, p-cpe:/a:centos:centos:nodejs24-full-i18n, p-cpe:/a:centos:centos:nodejs24-libs, p-cpe:/a:centos:centos:nodejs24-npm, p-cpe:/a:centos:centos:nodejs24, p-cpe:/a:centos:centos:nodejs26, p-cpe:/a:centos:centos:nodejs, p-cpe:/a:centos:centos:python-syspurpose, p-cpe:/a:centos:centos:rhsm-gtk, p-cpe:/a:centos:centos:sgx-common, p-cpe:/a:centos:centos:sgx-libs, p-cpe:/a:centos:centos:sgx-mpa, p-cpe:/a:centos:centos:sgx-pccs-admin, p-cpe:/a:centos:centos:sgx-pccs, p-cpe:/a:centos:centos:sgx-pckid-tool, p-cpe:/a:centos:centos:subscription-manager-cockpit, p-cpe:/a:centos:centos:subscription-manager-gui, p-cpe:/a:centos:centos:subscription-manager-initial-setup-addon, p-cpe:/a:centos:centos:subscription-manager-migration, p-cpe:/a:centos:centos:subscription-manager-plugin-container, p-cpe:/a:centos:centos:subscription-manager-plugin-ostree, p-cpe:/a:centos:centos:subscription-manager-rhsm-certificates, p-cpe:/a:centos:centos:subscription-manager-rhsm, p-cpe:/a:centos:centos:subscription-manager, p-cpe:/a:centos:centos:tdx-qgs, p-cpe:/a:debian:debian_linux:node-qs, p-cpe:/a:redhat:enterprise_linux:grafana-azure-monitor, p-cpe:/a:redhat:enterprise_linux:grafana-cloudwatch, p-cpe:/a:redhat:enterprise_linux:grafana-elasticsearch, p-cpe:/a:redhat:enterprise_linux:grafana-graphite, p-cpe:/a:redhat:enterprise_linux:grafana-influxdb, p-cpe:/a:redhat:enterprise_linux:grafana-loki, p-cpe:/a:redhat:enterprise_linux:grafana-mssql, p-cpe:/a:redhat:enterprise_linux:grafana-mysql, p-cpe:/a:redhat:enterprise_linux:grafana-opentsdb, p-cpe:/a:redhat:enterprise_linux:grafana-pcp, p-cpe:/a:redhat:enterprise_linux:grafana-postgres, p-cpe:/a:redhat:enterprise_linux:grafana-prometheus, p-cpe:/a:redhat:enterprise_linux:grafana-selinux, p-cpe:/a:redhat:enterprise_linux:grafana-stackdriver, p-cpe:/a:redhat:enterprise_linux:grafana, p-cpe:/a:redhat:enterprise_linux:librados-devel, p-cpe:/a:redhat:enterprise_linux:librados2, p-cpe:/a:redhat:enterprise_linux:libradospp-devel, p-cpe:/a:redhat:enterprise_linux:librbd-devel, p-cpe:/a:redhat:enterprise_linux:librbd1, p-cpe:/a:redhat:enterprise_linux:linux-sgx, p-cpe:/a:redhat:enterprise_linux:mozjs60-devel, p-cpe:/a:redhat:enterprise_linux:mozjs60, p-cpe:/a:redhat:enterprise_linux:nodejs-devel, p-cpe:/a:redhat:enterprise_linux:nodejs-docs, p-cpe:/a:redhat:enterprise_linux:nodejs-full-i18n, p-cpe:/a:redhat:enterprise_linux:nodejs-libs, p-cpe:/a:redhat:enterprise_linux:nodejs-npm, p-cpe:/a:redhat:enterprise_linux:nodejs22, p-cpe:/a:redhat:enterprise_linux:nodejs24-devel, p-cpe:/a:redhat:enterprise_linux:nodejs24-docs, p-cpe:/a:redhat:enterprise_linux:nodejs24-full-i18n, p-cpe:/a:redhat:enterprise_linux:nodejs24-libs, p-cpe:/a:redhat:enterprise_linux:nodejs24-npm, p-cpe:/a:redhat:enterprise_linux:nodejs24, p-cpe:/a:redhat:enterprise_linux:nodejs26, p-cpe:/a:redhat:enterprise_linux:nodejs, p-cpe:/a:redhat:enterprise_linux:python-syspurpose, p-cpe:/a:redhat:enterprise_linux:rhsm-gtk, p-cpe:/a:redhat:enterprise_linux:sgx-common, p-cpe:/a:redhat:enterprise_linux:sgx-libs, p-cpe:/a:redhat:enterprise_linux:sgx-mpa, p-cpe:/a:redhat:enterprise_linux:sgx-pccs-admin, p-cpe:/a:redhat:enterprise_linux:sgx-pccs, p-cpe:/a:redhat:enterprise_linux:sgx-pckid-tool, p-cpe:/a:redhat:enterprise_linux:subscription-manager-cockpit, p-cpe:/a:redhat:enterprise_linux:subscription-manager-gui, p-cpe:/a:redhat:enterprise_linux:subscription-manager-initial-setup-addon, p-cpe:/a:redhat:enterprise_linux:subscription-manager-migration, p-cpe:/a:redhat:enterprise_linux:subscription-manager-plugin-container, p-cpe:/a:redhat:enterprise_linux:subscription-manager-plugin-ostree, p-cpe:/a:redhat:enterprise_linux:subscription-manager-rhsm-certificates, p-cpe:/a:redhat:enterprise_linux:subscription-manager-rhsm, p-cpe:/a:redhat:enterprise_linux:subscription-manager, p-cpe:/a:redhat:enterprise_linux:tdx-qgs

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 8/29/2026

Reference Information

CVE: CVE-2026-82417