CVE
Webmin through 2.670 Privilege Escalation via acl/save_group.cgi
Webmin through 2.670 is affected, and the risk applies to users holding Webmin Users module access, such as delegated administrators. The facts do not name a fixed version.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fix or patch referenced
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. Attacker holds Webmin Users module access as a delegated administrator Webmin through 2.670 is affected
- 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
- 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? →
- 17/100 · 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
Summary
Webmin has a privilege escalation flaw in acl/save_group.cgi that lets a delegated administrator with Webmin Users module access grant themselves unauthorized modules, such as Command Shell, and then run commands as root. An attacker can reach it remotely over the network, but must already hold high-level privileges, and no user action is needed.
Read the original description
Webmin through 2.670 contains a privilege escalation vulnerability in acl/save_group.cgi that allows delegated administrators to grant unauthorized modules by submitting arbitrary module lists in the mod parameter. Attackers with Webmin Users module access can create or edit groups holding modules like Command Shell and assign themselves membership to execute commands as root.
Who should check
Teams running Webmin through 2.670 that delegate administration with the Webmin Users module
Read the source excerpt
“Webmin through 2.670 contains a privilege escalation vulnerability in acl/save_group.cgi”
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure8/25Specific setups only, reachable over the network
- Reach?/20Unknown. No tracked technology or package matched
- Severity8.6/10CVSS 8.6
- No patch0/5No signal
What would change the score
- Would score about 67 if added to CISA KEV
- Would score about 62 if CISA's SSVC rates exploitation active
- Would score about 24 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
Attacker holds Webmin Users module access as a delegated administrator Webmin through 2.670 is affectedApply the patch listed under Evidence.
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-2026-126780 (Webmin through 2.670 Privilege Escalation via acl/save_group.cgi), 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-2026-126780 (entry last updated 2026-11-11):
Affected:
- webmin webmin: through 2.670
Fixed versions: none listed yet.
Conditions (all must be true for the bug to be hit):
- Attacker holds Webmin Users module access as a delegated administrator (source: https://www.vulncheck.com/advisories/webmin-through-2.670-privilege-escalation-via-acl-save-group-cgi)
- Webmin through 2.670 is affected (source: https://www.vulncheck.com/advisories/webmin-through-2.670-privilege-escalation-via-acl-save-group-cgi)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: network access, high-privilege login, no user action.
CISA KEV: CVE-2026-126780 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-126780 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://github.com/webmin/webmin/commit/c861e308f4ee4cff1795ccc7621fc75623e1bb90
- https://github.com/webmin/webmin/commit/be54ba38c3b86a3647a62327e1de81d5d0db098a
- https://github.com/webmin/webmin/blob/2.670/acl/save_group.cgi#L83
- https://www.vulncheck.com/advisories/webmin-through-2.670-privilege-escalation-via-acl-save-group-cgi
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-2026-126780
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-2026-126780"}.Timeline
- CVE published
- First seen by cve.now
Affected versions
- webmin webmin
through 2.670
Evidence 6
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-126780
Is CVE-2026-126780 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. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
The flaw in acl/save_group.cgi lets a holder of Webmin Users module access create or edit groups. Such a user can grant unauthorized modules, such as Command Shell, to a group, add themselves to it, and then run commands as root.Source: vulncheck.com
Which versions are affected by CVE-2026-126780?
webmin: through 2.670.Source: cve.now feed data
Am I affected, and how do I check?
Webmin versions through 2.670 are listed as affected. The relevant setup is a user holding Webmin Users module access, such as a delegated administrator. To check, look at the installed Webmin version and review which accounts have Users module access in the Webmin ACL settings.Source: vulncheck.com
How do I fix CVE-2026-126780?
The checked facts do not name a fixed release or an upgrade target. Check the vendor's advisory for a version newer than 2.670 and install it once available.Source: vulncheck.com