EUVD-2026-41832
GHSA-29vj-9mgp-mwp2
Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Network-reachable via HTTP with no privileges; scope changes because SMTP credentials are exfiltrated to an external attacker-controlled system.
Primary rating from Vendor (apache).
CVSS VectorVendor: apache
Lifecycle Timeline
3Blast Radius
ecosystem impact- 14 maven packages depend on org.apache.camel:camel-mail (6 direct, 8 indirect)
Ecosystem-wide dependent count for version 4.0.0.
DescriptionCVE.org
Improper Input Validation, Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Apache Camel Mail Component.
The camel-mail producer (MailProducer.getSender) scanned the outgoing Exchange for message headers in the mail.smtp. / mail.smtps. namespace and, when any were present, built a per-message JavaMail sender with those values applied as JavaMail session properties, overriding the endpoint configuration. This namespace is Camel-internal - only MailProducer interprets it - and was not blocked by any HeaderFilterStrategy, so the values could originate from any inbound protocol (for example platform-http query parameters or request headers, or JMS / Kafka messages from untrusted producers) that feeds a route ending in an smtp / smtps producer without an intervening removeHeaders. The maximal impact is version-dependent: on releases before 4.19.0, setting mail.smtp.host redirects the SMTP connection to a server under the attacker's control, and because the producer then authenticates with the endpoint's configured username and password those credentials are transmitted to the attacker; on 4.19.0 and later the producer connects to the endpoint's configured host explicitly, so the reachable impact is limited to weakening transport security (for example mail.smtp.ssl.trust, mail.smtp.starttls.enable or mail.smtp.socks.host) and interception of the outgoing message rather than host redirect. Exploitation requires a route that channels untrusted input into the mail producer without stripping the namespace. 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, the per-message override is disabled by default; enable it only on trusted endpoints with useJavaMailSessionPropertiesFromHeaders=true. For deployments that cannot upgrade immediately, strip the namespace before the mail producer with removeHeaders('mail.smtp.*') and removeHeaders('mail.smtps.*') between any untrusted ingress and the smtp / smtps producer. Even with the opt-in enabled, route authors should still strip the namespace on any path that carries untrusted input.
AnalysisAI
Header injection in Apache Camel Mail Component enables attackers to override SMTP JavaMail session properties by supplying crafted headers in the mail.smtp./ mail.smtps. namespace through any untrusted inbound protocol - including HTTP query parameters, JMS, or Kafka - that feeds into a Camel route terminating at an SMTP producer. On releases before 4.19.0, the most severe impact is full SMTP host redirection: the producer reconnects to an attacker-controlled server and authenticates with the endpoint's configured credentials, resulting in credential theft. On 4.19.0 through pre-4.21.0, host redirection is blocked, but attackers can still weaken transport security (disabling STARTTLS, manipulating SSL trust, or injecting a SOCKS proxy) and intercept outgoing mail content. No public exploit identified at time of analysis, and this CVE is not listed in the CISA KEV catalog.
Technical ContextAI
Apache Camel is a widely-used Java integration framework implementing enterprise integration patterns. The affected component is the camel-mail producer (MailProducer.getSender), which historically scanned the outgoing Camel Exchange for message headers matching the mail.smtp.* and mail.smtps.* namespaces and applied them as per-message JavaMail Session properties, overriding the statically configured endpoint. The root cause (CWE-20, Improper Input Validation) is that no HeaderFilterStrategy blocked this namespace, so values originating from any upstream protocol - platform-http query parameters, inbound JMS or Kafka messages from untrusted producers - could flow unfiltered into the JavaMail session builder. Affected CPE: cpe:2.3:a:apache_software_foundation:apache_camel_mail:*:*:*:*:*:*:*:*. The differential impact by version stems from an internal change in 4.19.0 that hard-codes the SMTP host from the endpoint configuration, eliminating the host-redirect vector while leaving other JavaMail property overrides still reachable.
RemediationAI
The primary fix is to upgrade to a patched release: Apache Camel 4.21.0 (current), 4.14.8 (LTS stream), or 4.18.3, per the vendor advisory at https://camel.apache.org/security/CVE-2026-46584.html. After upgrading, per-message JavaMail property override is disabled by default; to re-enable it on trusted routes only, set useJavaMailSessionPropertiesFromHeaders=true on the endpoint explicitly. For deployments that cannot upgrade immediately, insert removeHeaders('mail.smtp.*') and removeHeaders('mail.smtps.*') steps between every untrusted inbound protocol and the smtp/smtps producer. This workaround is effective but requires identifying all route paths that carry externally influenced data - missing a single path leaves the application exposed. Note that even after upgrading with the opt-in flag enabled, route authors should still strip the namespace on paths carrying untrusted input to prevent the residual transport-security weakening vector.
Same weakness CWE-20 – Improper Input Validation
View allSame technique Information Disclosure
View allShare
External POC / Exploit Code
Leaving vuln.today