CVE-2022-36537
CVE-2022-36537 is a security flaw in ZK Framework AuUploader. Attackers can read information from ZK Framework AuUploader that should be private. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 27 Feb 2023, and says ransomware gangs have used it.[1]
ZK Framework AuUploader 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. ZK Framework has published a fix or advice.
Description
CISA calls it an unspecified in ZK Framework AuUploader. In its words: “ZK Framework AuUploader servlets contain an unspecified vulnerability that could allow an attacker to retrieve the content of a file located in the web context. The ZK Framework is an open-source Java framework. This vulnerability can impact multiple products, including but not limited to ConnectWise R1Soft Server Backup Manager.”[1]
The underlying weakness is CWE-441, in MITRE’s list of common software weaknesses.[2]
It scores 7.5 out of 10 on the Common Vulnerability Scoring System, which rates it high, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; ZK Framework’s advisory has them[3]. CISA names the product as ZK Framework AuUploader.
Most families won’t have ZK Framework AuUploader; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 27 Feb 2023, 185 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 20 Mar 2023 to fix it.[1] CISA says ransomware gangs have used it.
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 95%. 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
ZK Framework has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions.”[1]
- Check whether you use it.ZK Framework AuUploader 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 20 Mar 2023 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 7.5.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks, noting that ransomware gangs have used it.[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 95%.[4] |
References
- ^ Cybersecurity and Infrastructure Security Agency. “ZK Framework AuUploader Unspecified Vulnerability”. Known Exploited Vulnerabilities Catalog, added 27 Feb 2023.
- ^ National Institute of Standards and Technology. “CVE-2022-36537 Detail”. National Vulnerability Database, published 26 Aug 2022.
- ^ ZK Framework. Advisories and fixes: tracker.zkoss.org.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.954, percentile 99.9, 31 Oct 2026.
- CVE Program. “CVE-2022-36537”. 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.