CVE-2026-13573
Received Received - Intake

Stack-Based Buffer Overflow in LLVM ValueSymbolTable Module

Publication date: 2026-06-29

Last updated on: 2026-06-29

Assigner: VulDB

Description
A vulnerability was found in llvm llvm-project up to 22.1.6. This affects the function llvm::StringMap::insert in the library /lib/IR/ValueSymbolTable.cpp of the component ValueSymbolTable Module. The manipulation results in stack-based buffer overflow. Attacking locally is a requirement. The exploit has been made public and could be used. The project was informed of the problem early through an issue report but has not responded yet.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-06-29
Last Modified
2026-06-29
Generated
2026-06-29
AI Q&A
2026-06-29
EPSS Evaluated
N/A
NVD
CVE-2026-13573
EUVD
EUVD-2026-40115

Affected Vendors & Products

Showing 2 associated CPEs
Vendor Product Version / Range
llvm llvm_project to 22.1.6 (inc)
llvm llvm to 22.1.6 (inc)

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-119 The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
CWE-121 A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This vulnerability is a stack-based buffer overflow found in the LLVM project, specifically in the function llvm::StringMap::insert within the ValueSymbolTable module. It occurs when parsing malformed bitcode generated by a fuzzer, causing an out-of-bounds write on the stack during symbol table insertion. The issue arises from incorrect stack offset calculation for temporary values during the inlined execution of the insert function.

The vulnerability requires local access to exploit and can cause the program to abort due to an invalid stack read. It affects LLVM's ability to safely handle malformed input during bitcode parsing.

Impact Analysis

This vulnerability can lead to a stack-based buffer overflow when LLVM processes malformed bitcode, potentially causing the program to crash or abort unexpectedly. Since the exploit requires local access, an attacker with local privileges could trigger this overflow to disrupt the normal operation of LLVM-based tools or systems.

While the impact is limited by the need for local access, it could be used to cause denial of service or potentially aid in further exploitation depending on the environment and usage of LLVM components.

Detection Guidance

This vulnerability can be detected by building LLVM with AddressSanitizer enabled and running a proof-of-concept (PoC) fuzzer-generated malformed bitcode file using llvm-opt-fuzzer--x86_64-gvn. AddressSanitizer will detect the stack-buffer-overflow during the execution of the vulnerable function.

Specifically, the overflow is detected at line 113 of ValueSymbolTable.cpp during the inlined execution of llvm::StringMap::insert().

Suggested commands include compiling LLVM with AddressSanitizer flags and running the PoC bitcode file with llvm-opt-fuzzer to observe the crash or abort caused by the stack overflow.

Mitigation Strategies

The vulnerability requires local access to exploit and involves a stack-based buffer overflow in the llvm::StringMap::insert function during bitcode parsing.

Since the project has not yet responded with a fix, immediate mitigation steps include restricting local access to trusted users only and avoiding processing untrusted or malformed bitcode inputs that could trigger the vulnerability.

Additionally, building LLVM with AddressSanitizer enabled can help detect attempts to exploit this vulnerability during testing or development.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-13573. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart