CVE-2026-22321
Stack-Based Buffer Overflow in CLI Login Username Handling over CLI
No known exploitation. EPSS puts it in the 28th percentile. No fix published yet.
What to do
No fixed build or workaround is published yet. Limit exposure and watch for a patch.
What it is
From the CVE record
A stack-based buffer overflow in the device's Telnet/SSH CLI login routine occurs when a unauthenticated attacker send an oversized or unexpected username input. An overflow condition crashes the thread handling the login attempt, forcing the session to close. Because other CLI sessions remain unaffected, the impact is limited to a low‑severity availability disruption.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.4% chance of exploitation activity in the next 30 days, which ranks it in the 28th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
4 events over 0 days, from the signal feeds we watch.
- Publishedweakness classified, att&ck mapped, record updated
Affected products
And 69 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Scored 5.3 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity NoneNo integrity impact
- Availability LowReduced performance or intermittent disruption of service
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Privilege EscalationT1068Exploitation for Privilege Escalationhigh confidence
Sources
References in the record
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