CVE
OpsTree BuildPiper privilege escalation via unrestricted hostPath volumes
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
- Exploited
- Proof of concept public, per CISA
- Fix
- Fixed in 2.7.0
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. BuildPiper versions before 2.7.0
- Last modified
- Whether it needs action now or is a reference record, by fixed rules, with why. Last checked is when cve.now last re-read it.What do these mean? →
- Reference
- Last checked
- FIRST's estimate of the chance attackers exploit it in the next 30 days, updated daily.What do these mean? →
- 0.51% · 43rd percentile
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 33/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: poc
- Automatable: no
- Technical impact: total
Summary
OpsTree Solutions' BuildPiper, before the fixed release, lets an authenticated deploy user mount arbitrary Kubernetes hostPath volumes without any allow-list or policy check. Remotely, with only low-privilege login, an attacker can set the host path to / to mount the worker node's root filesystem read-write, breaking container isolation and potentially compromising the node and cluster.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
Original description
OpsTree BuildPiper before 2.7.0 contains an improper authorization vulnerability that allows authenticated deploy users to define arbitrary Kubernetes hostPath volumes without allow-list or policy checks. Attackers can set the host path to / in the Define HostPath Volume configuration to mount the worker node root filesystem read-write, breaking container isolation and enabling node and cluster compromise.
Who should check
Teams running OpsTree BuildPiper before 2.7.0 where authenticated deploy users can define Kubernetes hostPath volumes
“OpsTree BuildPiper before 2.7.0 contains an improper authorization vulnerability”
cve.now Index
- Exploitation15/40CISA rates a proof of concept as public
- Exposure8/25Specific setups only, reachable over the network
- Reach?/20Unknown. No tracked technology or package matched
- Severity10/10CVSS 9.4, total technical impact per CISA
- No patch0/5No signal
What would change the score
- Would score about 68 if added to CISA KEV
- Would score about 63 if CISA's SSVC rates exploitation active
- Would score about 40 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
BuildPiper versions before 2.7.0Upgrade to a fixed version: 2.7.0.
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-2026-127080 (OpsTree BuildPiper before 2.7.0 Container Escape via Unrestricted HostPath Volumes), 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-2026-127080 (entry last updated 2026-11-13):
Affected:
- OpsTree Solutions BuildPiper: fixed in 2.7.0
Fixed versions: 2.7.0.
Conditions (all must be true for the bug to be hit):
- BuildPiper versions before 2.7.0 (source: https://www.vulncheck.com/advisories/opstree-buildpiper-before-2.7.0-container-escape-via-unrestricted-hostpath-volumes)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: network access, low-privilege login, no user action.
CISA KEV: CVE-2026-127080 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-127080 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://www.buildpiper.io/
- https://www.vulncheck.com/advisories/opstree-buildpiper-before-2.7.0-container-escape-via-unrestricted-hostpath-volumes
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.
Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action.
Entry: https://cve.now/CVE-2026-127080
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example execute with name cve.get and arguments {"id": "CVE-2026-127080"}.Timeline
- CVE published
- First seen by cve.now
- Posted on X by cve.now
- CISA SSVC assessment
Exploitation: poc · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- OpsTree Solutions BuildPiper
fixed in 2.7.0
Evidence 5
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Public exploit code · 1
Establishes: Public exploit code exists (Exploit-DB, Metasploit, Nuclei and GitHub).
- Exploit
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-127080
Is CVE-2026-127080 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. CISA's SSVC assessment notes a proof of concept exists. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
BuildPiper allowed unrestricted hostPath volumes, so a container could mount the worker node's root filesystem read-write. That breaks container isolation and can let an attacker compromise the node and the wider cluster.Source: vulncheck.com
Which versions are affected by CVE-2026-127080?
BuildPiper: before 2.7.0.Source: cve.now feed data
Am I affected, and how do I check?
BuildPiper versions before 2.7.0 are affected. To check a deployment, look at the BuildPiper version in use and confirm it is 2.7.0 or later.Source: vulncheck.com
How do I fix CVE-2026-127080?
Upgrade BuildPiper to version 2.7.0 or later, which is the listed fixed version.Source: vulncheck.com