CVE-2025-34026: Versa Concerto Improper Authentication Vulnerability

Patch now

HIGH 7.5EXPLOITEDREMOTEUPGRADE

CVE-2025-34026 is a high-severity flaw (CVSS 7.5) affecting concerto, reported as exploited in the wild. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The Versa Concerto SD-WAN orchestration platform is vulnerable to an authentication bypass in the Traefik reverse proxy configuration, allowing at attacker to access administrative endpoints. The internal Actuator endpoint can be leveraged for access to heap dumps and trace logs.This issue is known to affect Concerto from 12.1.2 through 12.2.0. Additional versions may be vulnerable.

Why this priority

High severity
EPSS top 1%: very likely to be exploited
Exploited in the wild (CISA KEV)
Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	81.8% (top 1%)
CISA exploited list	Yes, fix due 2026-02-12
Weakness	CWE-288
Published	2025-05-21
Last modified	2026-06-17

Publisher (CNA): VulnCheck · Vendor: versa-networks

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2025-05-21 22:15 UTCPublished CVE record published
2026-01-22Exploited Added to the CISA Known Exploited Vulnerabilities list
2026-02-12Deadline CISA due date for US federal agencies to patch
2026-06-17 09:13 UTCUpdated Record last modified

versa-networks concerto UPGRADE

Affected: >= 11.4.0 and < 12.1.2 · 12.1.2 · 12.2.0

Fixed in: 12.1.2

Safe to downgrade to: a release before 11.4.0

1. Check installed version

apt-cache policy concerto || rpm -q concerto || concerto --version

2. UPGRADE to 12.1.2 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade concerto

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade concerto

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 11.4.0 (Debian / Ubuntu)

apt-cache madison concerto sudo apt install concerto=<VERSION_BEFORE_11.4.0> sudo apt-mark hold concerto

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list concerto sudo dnf downgrade concerto-<VERSION_BEFORE_11.4.0> sudo dnf versionlock add concerto

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Exact fixes by distribution

Fedora ELN · fips-provider-next · FIXED · 1.5.3-3.eln159 · FEDORA-2026-3ce99ec7df · source

sudo dnf upgrade --advisory=FEDORA-2026-3ce99ec7df

Fedora 46 · rubygem-webmock · FIXED · 3.26.1-3.fc46 · FEDORA-2026-bb57b4d095 · source

sudo dnf upgrade --advisory=FEDORA-2026-bb57b4d095

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Write-up: projectdiscovery.io/blog/versa-concerto-authentication-bypass-rce
Nuclei scan template: Versa Concerto Actuator Endpoint - Authentication Bypass

Verify at the official source NVD · CVE Program · CISA KEV catalog · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2025-34026?

concerto: upgrade to 12.1.2. Exact commands for each OS are on this page.

Is CVE-2025-34026 being exploited?

Yes. CVE-2025-34026 is on the CISA Known Exploited Vulnerabilities list, so treat it as patch-now.

What does CVE-2025-34026 affect?

CVE-2025-34026 affects concerto. Severity is high (CVSS 7.5). The Versa Concerto SD-WAN orchestration platform is vulnerable to an authentication bypass in the Traefik reverse proxy configuration, allowing at attacker to access administrative endpoints. The internal Actuator endpoint can be leveraged

How urgent is CVE-2025-34026?

Priority 86/100. High severity; EPSS top 1%: very likely to be exploited; Exploited in the wild (CISA KEV); Public exploit reference; Remotely exploitable, no login, no user action

Software pages

Traefik vulnerabilities

Related CVEs

CVE-2025-34027 CRITICAL 9.0 UPGRADE The Versa Concerto SD-WAN orchestration platform is vulnerable to an authentication bypass in the Traefik reve
CVE-2025-34025 HIGH 8.8 DOWNGRADE The Versa Concerto SD-WAN orchestration platform is vulnerable to an privileges escalation and container escap

References

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