CVE-2026-59141 in Data::RadixTree::Shared
Summary
by MITRE • 07/21/2026
Data::RadixTree::Shared versions before 0.02 for Perl allow an out-of-bounds read via unvalidated node and arena indices in rdx_find_locked.
The attach-time validator rdx_validate_header checks the header scalars and region layout against the file size, but does not validate the node records it then trusts. rdx_find_locked indexes nodes[cur].children[k] and reads each node's label_off and label_len raw from the mmap'd segment, none bounded against the node count or the arena size.
A local peer that can write the backing file can leave the header valid while poisoning the node records, so a lookup dereferences an out-of-bounds node or arena index, reading adjacent memory or crashing the process.
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Analysis
by VulDB Data Team • 07/21/2026
The vulnerability in Data::RadixTree::Shared versions prior to 0.02 represents a critical memory safety issue that arises from insufficient validation of node records during deserialization. This flaw exists within the rdx_find_locked function which processes radix tree lookups, where the system performs an out-of-bounds read due to unvalidated node and arena indices. The root cause stems from the attack-time validator rdx_validate_header which only verifies header scalars and region layout against file size but fails to validate the integrity of subsequent node records that are subsequently trusted and processed.
The technical implementation of this vulnerability occurs when the system maps a file into memory using mmap and then directly indexes into node arrays without proper bounds checking. Specifically, rdx_find_locked accesses nodes[cur].children[k] where k is derived from unvalidated input, while also reading label_off and label_len fields raw from the memory-mapped segment without verification against either the node count or arena size limits. This creates a scenario where an attacker with write access to the backing file can maintain valid header information while corrupting node records, leading to unpredictable memory access patterns.
The operational impact of this vulnerability extends beyond simple memory corruption, as it provides a pathway for local privilege escalation and potential information disclosure through adjacent memory reads. When the lookup operation dereferences out-of-bounds node or arena indices, the process may read sensitive data from adjacent memory locations or trigger segmentation faults that could be exploited to crash the application. This behavior aligns with CWE-125 which describes out-of-bounds read vulnerabilities, and represents a classic example of how insufficient input validation can lead to memory safety issues in parsing libraries.
Mitigation strategies for this vulnerability require multiple layers of defense including immediate patching to version 0.02 or later where proper node validation has been implemented, implementing additional bounds checking mechanisms during node record processing, and employing runtime protections such as address space layout randomization. The ATT&CK framework categorizes this issue under privilege escalation techniques where local attackers can leverage memory corruption vulnerabilities to gain elevated privileges. Additionally, developers should implement defensive programming practices that validate all input data structures before trusting their contents, particularly in libraries that process untrusted data files through memory mapping operations. Organizations should also consider implementing file integrity monitoring solutions to detect unauthorized modifications to critical library backing files.