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NVD / CVE Program· CNA redhat

CVE-2026-87766: Bubblewrap: bubblewrap: symlink traversal via /oldroot allows writing files outside sandbox during setup

Noroxi assessment

Priority: Monitor (action score 35/100)

  • 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: 0.21% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: azl3 bubblewrap 0.8.0-1 on Azure Linux 3.0 0.12.0-1.

Low priority for now. Upgrade to azl3 bubblewrap 0.8.0-1 on Azure Linux 3.0 0.12.0-1 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 bubblewrap. During sandbox setup, creating files or directories under the new root can follow a parent symlink onto the host via /oldroot, writing attacker-chosen paths outside the sandbox as the launching user. This happens before the sandboxed process starts. This issue is GHSA-pxhw-h44j-8pfx. It is fixed in bubblewrap 0.12.0.

HighCVSS 8.8 · v3.1—No exploit Fix available
Published
Sep 9, 2026
Updated
Nov 2, 2026
EPSS
0.2% · 11th percentile

Report tools

JSON

Action score

35

Monitor

Low priority for now.

CVSS
35 / 40 · 8.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · redhat
8.8
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.

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  • 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.

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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

    • 0:0.10.0-5.el10_2 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support

    • 0:0.10.0-3.el10_0.4 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 8

    • 0:0.4.0-3.el8_10 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support

    • 0:0.4.0-3.el8_4 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

    • 0:0.4.0-3.el8_4 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support

    • 0:0.4.0-3.el8_6 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

    • 0:0.4.0-3.el8_6 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service

    • 0:0.4.0-3.el8_8 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions

    • 0:0.4.0-3.el8_8 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 9

    • 0:0.6.3-1.el9_8.1 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

    • 0:0.4.1-7.el9_2.1 and laternot affected · rpm

  • Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

    • 0:0.4.1-7.el9_4.1 and laternot affected · rpm

Package-level exposure

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

EcosystemPackageAffected rangeFix
AlmaLinux:10bubblewrapbefore 0.10.0-5.el10_20.10.0-5.el10_2
AlmaLinux:8bubblewrapbefore 0.4.0-3.el8_100.4.0-3.el8_10
AlmaLinux:9bubblewrapbefore 0.6.3-1.el9_8.10.6.3-1.el9_8.1
Debian:12bubblewrapfrom 0—
Debian:13bubblewrapbefore 0.12.0-1~deb13u10.12.0-1~deb13u1
Debian:14bubblewrapbefore 0.12.0-10.12.0-1
openSUSE:Tumbleweedflatpakbefore 1.18.3-1.11.18.3-1.1
Red Hat:enterprise_linux_eus:10.0bubblewrapbefore 0:0.10.0-3.el10_0.40:0.10.0-3.el10_0.4
Red Hat:enterprise_linux_eus:10.0bubblewrap-debuginfobefore 0:0.10.0-3.el10_0.40:0.10.0-3.el10_0.4
Red Hat:enterprise_linux_eus:10.0bubblewrap-debugsourcebefore 0:0.10.0-3.el10_0.40:0.10.0-3.el10_0.4
Red Hat:enterprise_linux:10.2bubblewrapbefore 0:0.10.0-5.el10_20:0.10.0-5.el10_2
Red Hat:enterprise_linux:10.2bubblewrap-debuginfobefore 0:0.10.0-5.el10_20:0.10.0-5.el10_2
Red Hat:enterprise_linux:10.2bubblewrap-debugsourcebefore 0:0.10.0-5.el10_20:0.10.0-5.el10_2
Red Hat:enterprise_linux:8::baseosbubblewrapbefore 0:0.4.0-3.el8_100:0.4.0-3.el8_10
Red Hat:enterprise_linux:8::baseosbubblewrap-debuginfobefore 0:0.4.0-3.el8_100:0.4.0-3.el8_10
Red Hat:enterprise_linux:8::baseosbubblewrap-debugsourcebefore 0:0.4.0-3.el8_100:0.4.0-3.el8_10
Red Hat:enterprise_linux:9::baseosbubblewrapbefore 0:0.6.3-1.el9_8.10:0.6.3-1.el9_8.1
Red Hat:enterprise_linux:9::baseosbubblewrap-debuginfobefore 0:0.6.3-1.el9_8.10:0.6.3-1.el9_8.1
Red Hat:enterprise_linux:9::baseosbubblewrap-debugsourcebefore 0:0.6.3-1.el9_8.10:0.6.3-1.el9_8.1
Red Hat:rhel_aus:8.4::baseosbubblewrapbefore 0:0.4.0-3.el8_40:0.4.0-3.el8_4
Red Hat:rhel_aus:8.4::baseosbubblewrap-debuginfobefore 0:0.4.0-3.el8_40:0.4.0-3.el8_4
Red Hat:rhel_aus:8.4::baseosbubblewrap-debugsourcebefore 0:0.4.0-3.el8_40:0.4.0-3.el8_4
Red Hat:rhel_aus:8.6::baseosbubblewrapbefore 0:0.4.0-3.el8_60:0.4.0-3.el8_6
Red Hat:rhel_aus:8.6::baseosbubblewrap-debuginfobefore 0:0.4.0-3.el8_60:0.4.0-3.el8_6

+16

Same product

red hat: all records

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Published before and after this one in the same product

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    32Monitor

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
azl3 bubblewrap 0.8.0-1 on Azure Linux 3.00.12.0-1Microsoft (MSRC)
almalinux:bubblewrap0.4.0-3.el8_10 · AlmaLinux:8Package registry (OSV)
debian:bubblewrap0.12.0-1~deb13u1 · Debian:13Package registry (OSV)
opensuse:flatpak1.18.3-1.1 · openSUSE:TumbleweedPackage registry (OSV)
red hat:bubblewrap0:0.4.0-3.el8_10 · Red Hat:enterprise_linux:8::baseosPackage registry (OSV)
red hat:bubblewrap-debuginfo0:0.4.0-3.el8_10 · Red Hat:enterprise_linux:8::baseosPackage registry (OSV)
red hat:bubblewrap-debugsource0:0.4.0-3.el8_10 · Red Hat:enterprise_linux:8::baseosPackage registry (OSV)
rocky linux:bubblewrap0:0.4.0-3.el8_10 · Rocky Linux:8Package 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.

No dated events beyond publication.

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-2026-7965515 days apartSos: sos: path traversal in sos clean tar extraction via unvalidated symlink/hardlink targets leads to arbitrary file write
    31Monitor
  • CVE-2026-1183791 days apartAnsible-collection-ansible-posix: ansible.posix authorized_key: local privilege escalation via symlink-following chown
    29Monitor
  • CVE-2026-7269429 days apartMrtg: mrtg daemon symlink-following chown allows local privilege escalation via pid file path manipulation
    28Monitor
  • CVE-2026-9627918 days apartFlatpak: flatpak: path traversal issue in oci archive extraction via hardlinks
    26Monitor
  • CVE-2026-11180237 days apartNautilus: nautilus: arbitrary file deletion via trash symlink
    26Monitor
  • CVE-2026-11221040 days apartRhc: rhc: local privilege escalation via symlink following in rhc-canonical-facts.service
    24Monitor

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 with local access to the system 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
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted

Impact can extend beyond the vulnerable component (scope changes).

Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Changed
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-59 · Improper Link Resolution Before File Access ('Link Following')

CVSS vector

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

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.

Change log

  1. Fix✗ → ✓

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

References

Show all references (17 more)

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

All records