Skip to main content

Polkit CVE-2026-4897

| EUVDEUVD-2026-16214 MEDIUM
Allocation of Resources Without Limits or Throttling (CWE-770)
2026-03-26 secalert@redhat.com
Denial Of Service Red Hat Enterprise Linux Openshift Container Platform Polkit Freedesktop
5.5
CVSS 3.1 · Vendor: redhat
View

Vulnerability Assessment

Weakness
CWE
CWE-770
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V2 - Validation and Business Logic Resource allocation limits
MITRE ATT&CK

1 technique across 1 tactic: Impact

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

Sign in to read
Impact

The CVSS v3.1 score of 5.5 (AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H) reflects moderate severity with low complexity exploitation. Attack vector is local only, requiring authenticated user privileges (PR:L), but requires no user interaction and guarantees high availability impact. The SSVC framework indicates: (1) exploitation is not confirmed actively exploited via CISA KEV, (2) the attack is automatable (programmatic stdin flooding), (3) technical impact is denial of service (complete availability loss for affected services). While CVSS is elevated for DoS, the real-world risk depends on deployment model-systems with restricted local user access face lower risk. The lack of KEV confirmation and public exploit code suggests this is not yet weaponized, but the trivial attack mechanism (stdin flood) and low barrier to entry (local user, no complexity) make this a credible priority for environments with untrusted local users.
Exploit ScenarioDerived

A local user with shell access connects to a Linux system running vulnerable polkit and executes a simple script that pipes several gigabytes of data to polkit-agent-helper-1 via stdin, either directly or by triggering a polkit authentication prompt and flooding its input stream. The setuid binary attempts to buffer the entire input in memory without size validation, exhausting available RAM and causing the kernel OOM killer to terminate critical services, rendering the system unresponsive or offline. No public proof-of-concept code has been identified, but the exploit requires only basic shell scripting capability and no special tools.
This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).
Patch available 0.0% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Mar 26, 2026

Polkit's polkit-agent-helper-1 setuid binary fails to bound input length on stdin, allowing local authenticated users to trigger out-of-memory conditions and deny system availability. An attacker with local login privileges can supply excessively long input to exhaust memory resources, causing a system-wide denial of service. No public exploit code or active exploitation has been confirmed at the time of analysis.

RemediationAI

Consult the Red Hat security advisory (https://access.redhat.com/security/cve/CVE-2026-4897) and corresponding SUSE advisory for exact patched version numbers and upgrade instructions. Apply the vendor-released patch immediately to all systems running polkit with local user accounts. As an interim mitigation, restrict local shell access to trusted administrators only, disable polkit-agent-helper-1 if not required for the deployment use case, and monitor system memory and OOM events for signs of exploitation attempts. Implement resource limits (ulimit, cgroups) on user sessions to cap memory allocation per process, reducing the DoS impact scope.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Sign in to check
Technical ContextAI · show details

Polkit is a system authorization framework used across Linux distributions (including Red Hat and SUSE) to delegate privilege escalation decisions. The polkit-agent-helper-1 binary is a setuid-root helper component that handles authentication requests from the polkit daemon. The vulnerability stems from CWE-770 (Allocation of Resources Without Limits or Throttling), where the stdin input stream is read without enforcing maximum buffer or memory consumption limits. When a local user provides input larger than available system memory, the process attempts unbounded allocation, exhausting RAM and triggering OOM killer events that can crash critical system services. This affects the polkit authentication pipeline and represents a privilege escalation helper attack surface.

Know when Polkit gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources
Continue with Google Continue with GitHub

No credit card · 7-day full trial

Severity by source

Vendor (redhat) PRIMARY 5.5 MEDIUM
AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SUSE MEDIUM
Red Hat 5.5 MEDIUM

Primary rating from Vendor (redhat).

CVSS VectorVendor: redhat

Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Lifecycle Timeline

2
Patch released
Mar 31, 2026 - 21:13 nvd
Patch available
CVE Published
Mar 26, 2026 - 15:16 nvd
MEDIUM 5.5

DescriptionCVE.org

A flaw was found in polkit. A local user can exploit this by providing a specially crafted, excessively long input to the polkit-agent-helper-1 setuid binary via standard input (stdin). This unbounded input can lead to an out-of-memory (OOM) condition, resulting in a Denial of Service (DoS) for the system.

Executive ViewAI

Why It Matters

Organizations using A flaw should be aware of moderate risk from CVE-2026-4897 rated CVSS 5.5. Exploitation could compromise the security of affected deployments. Organizations should apply vendor updates when available and monitor for exploitation.

Business Impact: Low
Compensating Controls

Apply vendor patch. If patching is delayed: restrict network access and enable monitoring.

Threat Intelligence Overview

EPSS Score
0.0%
Top 98% exploitable
Data Quality
7 sources
Confidence: High
EUVD NVD CVE.org EPSS Vulnrichment Vendor VulDB

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity MEDIUM
CISA KEV No
Public POC No
EPSS 0.0%
Patch available Yes
Active threat No
Deciding rule
MEDIUM severity (CVSS 4.0-6.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision
Defer
Exploitation
None
System Exposure· derived
Small
Automatable
No
Human Impact
Low
Technical Impact
Partial

Priority Score

28
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +28
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Denial of Service MEDIUM

Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.

Affected Products (CPE)CVE.org

cpe:2.3:a:freedesktop:polkit:-:*:*:*:*:*:*:*
cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*

More in Polkit

View all
CVE-2018-19788 HIGH POC
8.8 Dec 03

A flaw was found in PolicyKit (aka polkit) 0.115 that allows a user with a uid greater than INT_MAX to successfully exec
CVE-2016-2568 HIGH
7.8 Feb 13

pkexec, when used with --user nonpriv, allows local users to escape to the parent session via a crafted TIOCSTI ioctl ca
CVE-2013-4288 HIGH
7.2 Oct 03

Race condition in PolicyKit (aka polkit) allows local users to bypass intended PolicyKit restrictions and gain privilege
CVE-2019-6133 MEDIUM
6.7 Jan 11

In PolicyKit (aka polkit) 0.115, the "start time" protection mechanism can be bypassed because fork() is not atomic, and
CVE-2015-3255 MEDIUM
4.6 Oct 26

The polkit_backend_action_pool_init function in polkitbackend/polkitbackendactionpool.c in PolicyKit (aka polkit) before
CVE-2015-4625 MEDIUM
4.6 Oct 26

Integer overflow in the authentication_agent_new_cookie function in PolicyKit (aka polkit) before 0.113 allows local use
CVE-2015-3256 MEDIUM
4.6 Oct 26

PolicyKit (aka polkit) before 0.113 allows local users to cause a denial of service (memory corruption and polkitd daemo
CVE-2018-1116 MEDIUM
4.4 Jul 10

A flaw was found in polkit before version 0.116. Rated medium severity (CVSS 4.4), this vulnerability is low attack comp
CVE-2015-3218 LOW
2.1 Oct 26

The authentication_agent_new function in polkitbackend/polkitbackendinteractiveauthority.c in PolicyKit (aka polkit) bef

Same weakness CWE-770 – Allocation of Resources Without Limits or Throttling

View all
CVE-2017-8779 HIGH POC
7.5
CVE-2025-53521 CRITICAL POC
9.3
CVE-2024-28182 MEDIUM
5.3
CVE-2023-2650 MEDIUM
6.5
CVE-2017-5850 HIGH POC
7.5
CVE-2025-26682 HIGH
7.5
CVE-2022-32206 MEDIUM POC
6.5
CVE-2023-24998 HIGH
7.5

Same technique Denial Of Service

View all
CVE-2015-5119 CRITICAL POC
9.8
CVE-2011-2462 CRITICAL POC
9.8
CVE-2011-0611 HIGH POC
8.8
CVE-2012-1889 HIGH POC
8.8
CVE-2012-0507 CRITICAL POC
9.8
CVE-2014-1761 HIGH POC
7.8
CVE-2015-5122 CRITICAL POC
9.8
CVE-2011-0609 HIGH POC
7.8

Vendor StatusVendor

Debian

policykit-1
Release Status Fixed Version Urgency
bullseye, bullseye (security) vulnerable 0.105-31+deb11u1 -
bookworm vulnerable 122-3 -
trixie vulnerable 126-2 -
forky, sid vulnerable 127-2 -
(unstable) fixed (unfixed) -

SUSE

Severity: Medium
Product Status
SUSE Linux Enterprise Desktop 15 SP7 Fixed
SUSE Linux Enterprise High Performance Computing 15 SP7 Fixed
SUSE Linux Enterprise Micro 5.2 Fixed
SUSE Linux Enterprise Micro 5.3 Fixed
SUSE Linux Enterprise Micro 5.4 Fixed

References

Advisories & patches
ADVISORY https://nvd.nist.gov/vuln/detail/CVE-2026-4897 ADVISORY https://ubuntu.com/security/notices/USN-8173-1 ADVISORY https://vuldb.com/vuln/353649 REF https://access.redhat.com/errata/RHSA-2026:59997 REF https://access.redhat.com/errata/RHSA-2026:66287 REF https://access.redhat.com/security/cve/CVE-2026-4897 REF https://bugzilla.redhat.com/show_bug.cgi?id=2451739

Search Externally

GitHub PoC Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC
Back

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy