SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2019-17558

Apache Solr VelocityResponseWriter Plug-In Remote Code Execution Vulnerability

KEVEXPLOIT ×2 ✓HIGH 7.5EPSS 98.6%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 3 May 2022). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

Description

Apache Solr 5.0.0 to Apache Solr 8.3.1 are vulnerable to a Remote Code Execution through the VelocityResponseWriter. A Velocity template can be provided through Velocity templates in a configset `velocity/` directory or as a parameter. A user defined configset could contain renderable, potentially malicious, templates. Parameter provided templates are disabled by default, but can be enabled by setting `params.resource.loader.enabled` by defining a response writer with that setting set to `true`. Defining a response writer requires configuration API access. Solr 8.4 removed the params resource loader entirely, and only enables the configset-provided template rendering when the configset is `trusted` (has been uploaded by an authenticated user).

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
98.57% probability · 100th percentile
Public exploits
2 in Exploit-DB · verified · first 1 November 2019
CISA KEV
Listed 3 November 2021 · due 3 May 2022
Weakness
CWE-74
Affected
apache/solr · oracle/primavera unifier
Source
security@apache.org
EPSS trend
0%50%100%30 October 2026: 98.57%30 October 202630 October 2026

EPSS 98.6% since 30 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

CISA notes

Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2019-17558

Public exploits (2)

Entries in Exploit-DB that cite this CVE. Links go to the Exploit-DB page and to the file in the public repository; nothing is hosted here. A verified tick means the Exploit-DB team confirmed the exploit works against the stated version.

EDB-IDTitleTypePublishedVerified
EDB-48338source ↗Apache Solr - Remote Code Execution via Velocity Template (Metasploit)multiple · Metasploitremote16 April 2020yes
EDB-47572source ↗Apache Solr 8.2.0 - Remote Code Executionjava · @l3x_wongwebapps1 November 2019no

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.