CVE
Red Hat Hardened Images unauthorized privileged file access in dnf5daemon-server
Affects Red Hat Hardened Images with dnf5daemon-server installed and its D-Bus service reachable by local users. No fixed version is listed; the workaround is to remove or disable dnf5daemon-server.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- See vendor advisory
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. dnf5daemon-server is installed, and its D-Bus service is reachable by local users.
- Published
- 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? →
- 28/100 · 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
A local attacker with low-level login access can exploit a flaw in the dnf5daemon-server component of the dnf5 package in Red Hat Hardened Images. By passing crafted URL or .rpm path patterns through unauthenticated D-Bus methods, the attacker can make a root-privileged package loader fetch or open local paths, which can disclose privileged content or exhaust disk space to deny service.
Read the original description
A flaw was found in dnf5daemon-server. Unauthenticated D-Bus methods pass caller-controlled URL or .rpm path patterns into a root-privileged cmdline package loader that may store fetched content in a world-readable cache without size limits, or open local paths as root, allowing a local attacker to disclose privileged content and to deny service via disk exhaustion.
Who should check
Teams running systems with dnf5daemon-server installed, such as Red Hat Hardened Images, where the daemon's D-Bus service is available to local users.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure5/25Specific setups only
- Reach10/20Shipped in major Linux distributions
- Severity8.4/10CVSS 8.4
- No patch5/5No fixed version listed; see vendor advisory
What would change the score
- Would score about 78 if added to CISA KEV
- Would score about 73 if CISA's SSVC rates exploitation active
- Would score about 38 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
dnf5daemon-server is installed, and its D-Bus service is reachable by local users.Workaround: Remove or disable dnf5daemon-server, or restrict system D-Bus access to org.rpm.dnf.v0 to trusted users.
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-2026-123177 (Dnf5: dnf5daemon-server: dnf5daemon-server: unauthenticated privileged cmdline package fetch/open via add_cmdline_packages), 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-2026-123177 (entry last updated 2026-11-13):
Affected:
- Red Hat Red Hat Hardened Images: version range not reported
Fixed versions: none listed yet.
Conditions (all must be true for the bug to be hit):
- dnf5daemon-server is installed, and its D-Bus service is reachable by local users. (source: https://access.redhat.com/security/cve/cve-2026-123177)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: local access, low-privilege login, no user action.
Workaround: Remove or disable dnf5daemon-server, or restrict system D-Bus access to org.rpm.dnf.v0 to trusted users. (source: https://www.cve.org/CVERecord?id=CVE-2026-123177)
CISA KEV: CVE-2026-123177 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-123177 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://bugzilla.redhat.com/show_bug.cgi?id=2567426
- https://access.redhat.com/security/cve/CVE-2026-123177
- https://www.cve.org/CVERecord?id=CVE-2026-123177
- https://access.redhat.com/security/cve/cve-2026-123177
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-2026-123177
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-2026-123177"}.Timeline
- CVE published
- First seen by cve.now
Affected versions
- dnf5
Version range not reported
Evidence 4
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Write-ups · 1
Establishes: Technical detail and context.
- Report
Other links · 1
- Link
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-123177
Is CVE-2026-123177 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?
A local user can reach the root-run dnf5daemon-server and have it open or fetch packages from the command line without authentication. This can disclose privileged content the daemon can read and can deny service by exhausting disk space.Source: access.redhat.com, cve.org
Am I affected, and how do I check?
The issue requires dnf5daemon-server to be installed and its D-Bus service to be reachable by local users. The checked facts do not list affected versions, so check whether the package is installed on the system.Source: access.redhat.com, cve.org
How do I fix CVE-2026-123177?
No fixed version or vendor patch ID is listed. Remove or disable dnf5daemon-server, or restrict system D-Bus access to org.rpm.dnf.v0 to trusted users.Source: access.redhat.com, cve.org
What if there's no patch?
While no fix is listed, remove or disable dnf5daemon-server if GNOME Software or dnf5daemon-client is not required. Otherwise, restrict system D-Bus access to org.rpm.dnf.v0 to trusted users.Source: access.redhat.com, cve.org
Why do the sources disagree?
The description calls the issue unauthenticated, but the CVSS vector lists PR:L, which means privileges are required. The sources do not resolve this difference.Source: access.redhat.com, cve.org