CVE-2026-48203: Apache Camel-Solr: The SolrParam. and SolrField. Exchange header prefixes used non-Camel-prefixed names that bypass the HTTP header filter, allowing an HTTP client to inject Solr query parameters (server-side request forgery) and document fields

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 0.6%, percentile 48: FIRST’s model estimates a 0.6% chance of exploitation activity in the next 30 days, higher than 48% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes org.apache.camel:camel-solr (Maven) >= 4.0.0, < 4.14.8, fixed in 4.14.8; org.apache.camel:camel-solr (Maven) >= 4.15.0, < 4.18.3, fixed in 4.18.3; org.apache.camel:camel-solr (Maven) >= 4.19.0, < 4.21.0, fixed in 4.21.0. Check your lockfile, including transitive dependencies.

What it is

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection'), Improper Input Validation, Server-Side Request Forgery (SSRF) vulnerability in Apache Camel Solr component. The camel-solr producer copies Exchange message headers whose names begin with the SolrParam. prefix into the parameters of the Solr request, and headers whose names begin with the SolrField. prefix into the fields of the indexed Solr document. The prefix constants (SolrConstants.HEADERPARAMPREFIX / HEADERFIELDPREFIX) were the plain strings SolrParam. / SolrField.. Because these names do not start with the Camel / camel prefix, HttpHeaderFilterStrategy - which blocks only the Camel header namespace on the HTTP boundary - let them pass from an inbound HTTP request straight into the Exchange. In a route that bridges an HTTP consumer (for example platform-http) into a solr: producer, any HTTP client could therefore set SolrParam. headers to inject arbitrary Solr request parameters - including shards or stream.url, which cause the Solr server to issue server-side requests to an attacker-chosen URL (server-side request forgery, for example to an internal service or a cloud metadata endpoint), or qt to reach administrative request handlers - and set SolrField. headers to inject arbitrary fields into indexed documents. No credentials are required when the bridging consumer is unauthenticated. This issue affects Apache Camel: from 4.0.0 before 4.14.8, from 4.15.0 before 4.18.3, from 4.19.0 before 4.21.0. Users are recommended to upgrade to version 4.21.0, which fixes the issue. If users are on the 4.14.x LTS releases stream, then they are suggested to upgrade to 4.14.8. If users are on the 4.18.x releases stream, then they are suggested to upgrade to 4.18.3. After upgrading, routes that set Solr parameters or fields via the raw header prefixes must use CamelSolrParam. / CamelSolrField. instead of SolrParam. / SolrField.. For deployments that cannot upgrade immediately, strip the SolrParam. and SolrField. headers from any untrusted ingress before the solr: producer, and set the required Solr parameters and fields from a trusted source in the route.

From the GitHub advisory

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection'), Improper Input Validation, Server-Side Request Forgery (SSRF) vulnerability in Apache Camel Solr component.

The camel-solr producer copies Exchange message headers whose names begin with the SolrParam. prefix into the parameters of the Solr request, and headers whose names begin with the SolrField. prefix into the fields of the indexed Solr document. The prefix constants (SolrConstants.HEADERPARAMPREFIX / HEADERFIELDPREFIX) were the plain strings SolrParam. / SolrField.. Because these names do not start with the Camel / camel prefix, HttpHeaderFilterStrategy - which blocks only the Camel header namespace on the HTTP boundary - let them pass from an inbound HTTP request straight into the Exchange. In a route that bridges an HTTP consumer (for example platform-http) into a solr: producer, any HTTP client could therefore set SolrParam. headers to inject arbitrary Solr request parameters - including shards or stream.url, which cause the Solr server to issue server-side requests to an attacker-chosen URL (server-side request forgery, for example to an internal service or a cloud metadata endpoint), or qt to reach administrative request handlers - and set SolrField. headers to inject arbitrary fields into indexed documents. No credentials are required when the bridging consumer is unauthenticated. This issue affects Apache Camel: from 4.0.0 before 4.14.8, from 4.15.0 before 4.18.3, from 4.19.0 before 4.21.0.

Users are recommended to upgrade to version 4.21.0, which fixes the issue. If users are on the 4.14.x LTS releases stream, then they are suggested to upgrade to 4.14.8. If users are on the 4.18.x releases stream, then they are suggested to upgrade to 4.18.3. After upgrading, routes that set Solr parameters or fields via the raw header prefixes must use CamelSolrParam. / CamelSolrField. instead of SolrParam. / SolrField.. For deployments that cannot upgrade immediately, strip the SolrParam. and SolrField. headers from any untrusted ingress before the solr: producer, and set the required Solr parameters and fields from a trusted source in the route.

Weakness type: CWE-74, CWE-20, CWE-918.

Product: org.apache.camel:camel-solr (Maven) · Assigned by: apache · Published: 2026-07-06

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.60% probability of exploitation activity in the next 30 days; percentile 48.

Timeline

• 2026-07-06 — CVE record last updated
• 2026-07-06 — CVE record published by apache
• 2026-07-06 — GitHub-reviewed advisory GHSA-4h4f-v54q-7pq8 published (critical)

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vendor and project advisories, patches

1. camel.apache.org camel.apache.org

Vulnerability records

1. GitHub Advisory GHSA-4h4f-v54q-7pq8 github.com
2. CVE.org record CVE-2026-48203 cve.org
3. NVD entry CVE-2026-48203 nvd.nist.gov

Other references from the CVE record and advisory

1. openwall.com openwall.com
2. github.com github.com
3. github.com github.com
4. github.com github.com
5. github.com github.com
6. github.com github.com
7. github.com github.com
8. github.com github.com
9. github.com github.com
10. github.com github.com
11. issues.apache.org issues.apache.org

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