CVE-2022-26143
CVE-2022-26143 is a security flaw in Mitel MiCollab, MiVoice Business Express. Attackers can reach parts of Mitel MiCollab, MiVoice Business Express that should be locked to them. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 25 Mar 2022.[1]
Mitel MiCollab, MiVoice Business Express is business software or equipment. Most families won’t have it, but attackers break into it to get inside companies, and from there to what those companies hold about their customers, patients and staff. Mitel has published a fix or advice.
Description
CISA calls it an access control in Mitel MiCollab, MiVoice Business Express. In its words: “A vulnerability has been identified in MiCollab and MiVoice Business Express that may allow a malicious actor to gain unauthorized access to sensitive information and services, cause performance degradations or a denial of service condition on the affected system.”[1]
The CVE record adds: “The TP-240 (aka tp240dvr) component in Mitel MiCollab before 9.4 SP1 FP1 and MiVoice Business Express through 8.1 allows remote attackers to obtain sensitive information and cause a denial of service (performance degradation and excessive outbound traffic). This was exploited in the wild in February and March 2022 for the TP240PhoneHome DDoS attack.”[2]
The underlying weakness is missing authentication (CWE-306), CWE-406, in MITRE’s list of common software weaknesses.
It scores 9.8 out of 10 on the Common Vulnerability Scoring System, which rates it critical, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; Mitel’s advisory has them[3]. CISA names the product as Mitel MiCollab, MiVoice Business Express.
Most families won’t have Mitel MiCollab, MiVoice Business Express; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 25 Mar 2022, 15 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 15 Apr 2022 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 87%. That’s in the top 1% of the flaws it scores.[4]
CISA assesses it as automatable: attackers can run it against many targets at once.
CISA doesn’t say who was attacked, or how.
Fix
Mitel has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions.”[1]
- Check whether you use it.Mitel MiCollab, MiVoice Business Express is business software or equipment, so most families won’t have it. If you run a business, or work from home on company equipment, ask whoever looks after your IT.
- Send this page to your IT person.Ask them to confirm it’s fixed, or not in use. CISA gave US government agencies until 15 Apr 2022 to fix it.
- If it can’t be fixed, take it offline.CISA’s advice when there’s no fix is to stop using the product, or take it off the internet, until there is one.
You can’t fix someone else’s server, but you can watch for what follows a break-in like this: a breach notice, a password reset you didn’t ask for, or a scam message that knows things it shouldn’t. HARD watches for those for you and your family.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 9.8.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 87%.[4] |
See also
Other Mitel flaws
- CVE-2024-41710, Mitel SIP Phones: argument injection ·
- CVE-2024-55550, Mitel MiCollab: path traversal ·
- CVE-2024-41713, Mitel MiCollab: path traversal ·
- CVE-2022-41223, Mitel MiVoice Connect: code injection ·
- CVE-2022-40765, Mitel MiVoice Connect: command injection ·
Other missing authentication flaws
- CVE-2026-111357, Ivanti Connect Secure: missing authentication for critical function ·
- CVE-2026-67277, MikroTik RouterOS: missing authentication for critical function ·
- CVE-2026-81578, PaperCut NG/MF: missing authentication for critical function ·
- CVE-2026-72529, TrueConf Server: missing authentication for critical function ·
- CVE-2026-56164, Microsoft SharePoint Server: missing authentication for critical function ·
Added the same day
- CVE-2022-26318, WatchGuard Firebox and XTM Appliances: arbitrary code execution ·
- CVE-2022-21999, Microsoft Windows: print spooler privilege escalation ·
- CVE-2021-42237, Sitecore XP: remote command execution ·
- CVE-2021-22941, Citrix ShareFile: improper access control ·
- CVE-2020-9377, D-Link DIR-610 Devices: remote command execution ·
Every Mitel flaw on CISA’s list · Everything added in March 2022
References
- ^ Cybersecurity and Infrastructure Security Agency. “MiCollab, MiVoice Business Express Access Control Vulnerability”. Known Exploited Vulnerabilities Catalog, added 25 Mar 2022.
- ^ National Institute of Standards and Technology. “CVE-2022-26143 Detail”. National Vulnerability Database, published 10 Mar 2022.
- ^ Mitel. Advisories and fixes: blog.cloudflare.com, akamai.com, mitel.com, shadowserver.org.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.873, percentile 99.8, 31 Oct 2026.
- CVE Program. “CVE-2022-26143”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.