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NVD / CVE Program· CNA redhat

CVE-2026-85498: Polkit: regression in cve-2026-4897 fix (polkit read_cookie()) - stack buffer underflow

Noroxi assessment

Priority: Monitor (action score 14/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.26% (FIRST EPSS).
  • Someone on the same network segment can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: polkit (openSUSE:Tumbleweed) 128-1.1; polkit (Red Hat:hummingbird:1) 0:127-5.1.hum1; polkit-devel (Red Hat:hummingbird:1) 0:127-5.1.hum1.

Low priority for now. Upgrade to polkit (openSUSE:Tumbleweed) 128-1.1; polkit (Red Hat:hummingbird:1) 0:127-5.1.hum1; polkit-devel (Red Hat:hummingbird:1) 0:127-5.1.hum1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A flaw was found in polkit. When processing input that begins with a null byte, an arithmetic error in the authentication agent helper causes an integer underflow during buffer length calculation, resulting in an out-of-bounds memory read. An attacker capable of supplying crafted input can trigger this flaw, potentially causing an application crash and resulting in a Denial of Service (DoS).

LowCVSS 3.5 · v3.1—No exploit Fix available
Published
Oct 29, 2026
Updated
Oct 30, 2026
EPSS
0.2% · 18th percentile

Report tools

JSON

Action score

14

Monitor

Low priority for now.

CVSS
14 / 40 · 3.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · redhat
3.5
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-85498

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.

  • Red Hat Red Hat Enterprise Linux 10

    • all versionsaffected
    • all versionsaffected

  • Red Hat Red Hat Enterprise Linux 6

    • all versionsaffected
    • all versionsaffected

  • Red Hat Red Hat Enterprise Linux 7

    • all versionsaffected
    • all versionsaffected
    • all versionsaffected
    • all versionsaffected

  • Red Hat Red Hat Enterprise Linux 8

    • all versionsaffected
    • all versionsaffected

  • Red Hat Red Hat Enterprise Linux 9

    • all versionsaffected
    • all versionsaffected

  • Red Hat Red Hat Hardened Images

    • 127-5.1.hum1 and laternot affected · rpm

  • Red Hat Red Hat OpenShift Container Platform 4

    • all versionsaffected
    • all versionsaffected

  • Red Hat Red Hat OpenShift Container Platform 5

    • all versionsaffected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:14policykit-1from 0—
openSUSE:Tumbleweedpolkitbefore 128-1.1128-1.1
Red Hat:hummingbird:1polkitbefore 0:127-5.1.hum10:127-5.1.hum1
Red Hat:hummingbird:1polkit-develbefore 0:127-5.1.hum10:127-5.1.hum1
Red Hat:hummingbird:1polkit-docsbefore 0:127-5.1.hum10:127-5.1.hum1
Red Hat:hummingbird:1polkit-libsbefore 0:127-5.1.hum10:127-5.1.hum1

Same product

red hat: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-90954Busybox: busybox: dpkg-deb extraction-root escape via per-ar-member deferred symlink flush
    31Monitor
  • CVE-2026-96512Sudo: sudo: tz environment variable allows bypass of notbefore/notafter time-based authorization
    31Monitor
  • CVE-2026-78410Util-linux: util-linux: restricted bind mounts do not pin the source, allowing x-mount.owner/group/mode redirection
    31Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-88838Oct 13, 2026 · Busybox: busybox: non-root mount option filter bypass allows clearing fstab security restrictions
    22Monitor
  • ← EarlierCVE-2026-88829Oct 14, 2026 · Busybox: busybox: http request smuggling via pipelined requests in httpd reverse proxy
    28Monitor
  • ← EarlierCVE-2026-88842Oct 14, 2026 · Busybox: busybox: dpkg stale field_start pointer causes out-of-bounds read and status file corruption
    13Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
opensuse:polkit128-1.1 · openSUSE:TumbleweedPackage registry (OSV)
red hat:polkit0:127-5.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:polkit-devel0:127-5.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:polkit-docs0:127-5.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:polkit-libs0:127-5.1.hum1 · Red Hat:hummingbird:1Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. Fix recorded+1 d
  3. TodayNov 5, 2026+7 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-8883536 days apartBusybox: busybox: dpkg read_package_field() steps past nul terminator, causing out-of-bounds read on malformed .deb packages
    24Monitor
  • CVE-2026-1500394 days apartBinutils: gnu binutils: heap-buffer-overflow in linker leads to information disclosure and denial of service
    22Monitor
  • CVE-2026-4367135 days apartLibxpm: libxpm: denial of service via out-of-bounds read in xpm file parsing
    22Monitor
  • CVE-2026-8884036 days apartBusybox: busybox: tls ssl_server reads one byte out of bounds when parsing truncated clienthello
    21Monitor
  • CVE-2026-8787550 days apartCups: openprinting cups: heap out-of-bounds read in cupsutf32toutf8() via missing source-length bound
    17Monitor
  • CVE-2026-8884215 days apartBusybox: busybox: dpkg stale field_start pointer causes out-of-bounds read and status file corruption
    13Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone on the same network segment can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
low · the service can be disrupted
Attack vector
Adjacent
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
Low

Weakness class (CWE)

CWE-125 · Out-of-bounds Read

CVSS vector

CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓
  2. SSVC exploitation— → none
  3. Exploit maturity— → none

For records you follow, these changes also arrive as notifications. →

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records