Improper Control of Dynamically-Managed Code Resources, Unrestricted Upload of File with Dangerous Type, Inclusion of Functionality from Untrusted Control Sphere vulnerability in Apache Solr.This issue affects Apache Solr: from 6.0.0 through 8.11.2, from 9.0.0 before 9.4.1.
In the affected versions, Solr ConfigSets accepted Java jar and class files to be uploaded through the ConfigSets API.
When backing up Solr Collections, these configSet files would be saved to disk when using the LocalFileSystemRepository (the default for backups).
If the backup was saved to a directory that Solr uses in its ClassPath/ClassLoaders, then the jar and class files would be available to use with any ConfigSet, trusted or untrusted.
When Solr is run in a secure way (Authorization enabled), as is strongly suggested, this vulnerability is limited to extending the Backup permissions with the ability to add libraries.
Users are recommended to upgrade to version 8.11.3 or 9.4.1, which fix the issue.
In these versions, the following protections have been added:
* Users are no longer able to upload files to a configSet that could be executed via a Java ClassLoader.
* The Backup API restricts saving backups to directories that are used in the ClassLoader.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (9.0): severity, escalated by confirmed exploitation. This CVE's 9.0 is EPSS's lift toward 9.0 from its impact severity (EG Severity, CVSS 8.8 HIGH): a likelihood of exploitation, not impact.
- EG Severity
- 8.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 84% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track* at medium mission impactTrack at low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.
A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it