CVE-2018-1000861
CVE-2018-1000861 is a security flaw in Jenkins Stapler Web Framework. Attackers can run their own code on Jenkins Stapler Web Framework. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 10 Feb 2022.[1]
Jenkins Stapler Web Framework 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. Jenkins has published a fix or advice.
Description
CISA calls it a stapler web framework deserialization of untrusted data in Jenkins Jenkins Stapler Web Framework. In its words: “A code execution vulnerability exists in the Stapler web framework used by Jenkins”[1]
The CVE record adds: “A code execution vulnerability exists in the Stapler web framework used by Jenkins 2.153 and earlier, LTS 2.138.3 and earlier in stapler/core/src/main/java/org/kohsuke/stapler/MetaClass.java that allows attackers to invoke some methods on Java objects by accessing crafted URLs that were not intended to be invoked this way.”[2]
The underlying weakness is deserialization of untrusted data (CWE-502), 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; Jenkins’s advisory has them[3]. CISA names the product as Jenkins Jenkins Stapler Web Framework.
Most families won’t have Jenkins Stapler Web Framework; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 10 Feb 2022, 1,158 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 10 Aug 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 98%. 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
Jenkins has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions.”[1]
- Check whether you use it.Jenkins Stapler Web Framework 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 10 Aug 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 98%.[4] |
See also
Other Jenkins flaws
- CVE-2017-1000353, Jenkins: remote code execution ·
- CVE-2024-23897, Jenkins Command Line Interface (CLI): command line interface (CLI) path traversal ·
- CVE-2015-5317, Jenkins User Interface (UI): user interface (UI) information disclosure ·
- CVE-2019-1003029, Jenkins Script Security Plugin: sandbox bypass ·
- CVE-2019-1003030, Jenkins Matrix Project Plugin: remote code execution ·
Other deserialization of untrusted data flaws
- CVE-2021-23758, Ajax.NET Professional: deserialization of untrusted data ·
- CVE-2026-63077, JetBrains TeamCity: deserialization of untrusted data ·
- CVE-2026-50522, Microsoft SharePoint: deserialization of untrusted data ·
- CVE-2026-58644, Microsoft SharePoint: deserialization of untrusted data ·
- CVE-2026-45659, Microsoft SharePoint Server: deserialization of untrusted data ·
Added the same day
- CVE-2021-36934, Microsoft Windows: SAM local privilege escalation ·
- CVE-2020-0796, Microsoft SMBv3: remote code execution ·
- CVE-2017-9791, Apache Struts 1: improper input validation ·
- CVE-2017-8464, Microsoft Windows: shell (.lnk) remote code execution ·
- CVE-2017-10271, Oracle WebLogic Server: corporation webLogic server remote code execution ·
Every Jenkins flaw on CISA’s list · Everything added in February 2022
References
- ^ Cybersecurity and Infrastructure Security Agency. “Jenkins Stapler Web Framework Deserialization of Untrusted Data Vulnerability”. Known Exploited Vulnerabilities Catalog, added 10 Feb 2022.
- ^ National Institute of Standards and Technology. “CVE-2018-1000861 Detail”. National Vulnerability Database, published 10 Dec 2018.
- ^ Jenkins. Advisories and fixes: jenkins.io.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.983, percentile 99.9, 31 Oct 2026.
- CVE Program. “CVE-2018-1000861”. 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.