High

Unsafe deserialization via trusted-package matching in Spring for Apache Pulsar JsonPulsarHeaderMapper

IdentifiersCVE-2026-41732CWE-502· Deserialization of Untrusted Data

CVE-2026-41732 is a high-severity unsafe deserialization issue in Spring for Apache Pulsar affecting JsonPulsarHeaderMapper. The mapper validated type headers against configured trusted packages using a prefix-based check, so trusting a package also implicitly trusted all of its subpackages. In addition, if trusted-packages was configured as empty, the implementation fell back to trusting all packages instead of enforcing a safe default allow-list. In environments using header-based type mapping together with Jackson bean deserialization, a malicious Pulsar producer can send crafted header values that cause a consumer to deserialize unintended types, including arbitrary JDK classes with constructors or initialization behavior that may have side effects. Affected versions are 2.0.0 through 2.0.5, 1.2.0 through 1.2.17, and 1.1.0 through 1.1.17.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation can cause a vulnerable consumer to deserialize attacker-influenced types that should not have been permitted by the trusted-packages policy. According to the provided content, this can include arbitrary JDK classes whose constructors may perform side effects such as allocating file descriptors or spawning thread pools. Depending on the reachable gadget/type set and application behavior, the result can include compromise of confidentiality, integrity, and availability, including unsafe object creation, resource exhaustion, and potentially broader code-execution-adjacent deserialization impacts.

Mitigation

If you can’t patch tonight, do this now.

If immediate upgrade is not possible, constrain trusted-packages as narrowly as possible, do not leave trusted-packages empty, and avoid configurations that permit broad header-driven type resolution. Restrict message production to trusted producers, isolate or authenticate Pulsar producers where possible, and apply defense-in-depth controls around deserialization and message handling on consumers until fixed versions are deployed. However, the vendor guidance in the provided content indicates upgrading is the primary corrective action.

Remediation

Patch, then assume compromise.

Upgrade Spring for Apache Pulsar to a fixed release. The provided content identifies 2.0.6 as the OSS fix for the 2.0.x branch, 1.2.18 as the OSS fix for the 1.2.x branch, and 1.1.18 as a fix for the 1.1.x branch. Commercial patch releases referenced in the content include 2.0.5.1 and 1.2.17.1. Spring stated that no further mitigation steps are necessary beyond upgrading.

PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType

BroadcomSpring For Apache Pulsarapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

6 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

6 SOURCESView more in app

security online infoNews

Jun 11, 2026

Spring GraphQL Security Patches for Deserialization Flaws

An input validation defect in messaging components affecting header configuration handling, enabling arbitrary class execution through crafted headers.

cvefeed high severityNews

Jun 10, 2026

CVE-2026-41732 - In Spring for Apache Pulsar, overly broad trusted-package matching in header mapper exposes JDK classes to deserialization

A vulnerability in Spring for Apache Pulsar where JsonPulsarHeaderMapper improperly trusted packages due to prefix-based matching and unsafe fallback behavior for empty trusted-packages configuration, potentially enabling unsafe deserialization-related impacts.

springNews

Jun 9, 2026

CVE-2026-41732: In Spring for Apache Pulsar, overly broad trusted-package matching in header mapper exposes JDK classes to deserialization

A deserialization-related vulnerability in Spring for Apache Pulsar caused by overly broad trusted-package matching and unsafe fallback behavior, allowing crafted header values to trigger deserialization of arbitrary JDK types.

What this page doesn’t show

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity3

Community discussion across Reddit, Mastodon, and other social sources.

EXTERNAL REFERENCES

MITRE CVE

cve.org · CVE-2026-41732

NVD

nvd.nist.gov/vuln/detail/CVE-2026-41732

MITRE CWE · CWE-502

Deserialization of Untrusted Data

spring.io

spring.io/security/cve-2026-41732