EUVD-2026-40118
GHSA-pf97-7r98-qpj7
Severity by source
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Local low-privilege access required to pass crafted bitcode; scope unchanged and impact limited to process crash with no confidentiality or integrity effect.
Primary rating from Vendor (VulDB).
CVSS VectorVendor: VulDB
Lifecycle Timeline
3DescriptionCVE.org
A vulnerability was determined in llvm llvm-project up to 22.1.6. This impacts the function GCRelocateInst::getBasePtr in the library llvm/lib/IR/IntrinsicInst.cpp of the component Bitcode File Handler. This manipulation causes heap-based buffer overflow. It is possible to launch the attack on the local host. The exploit has been publicly disclosed and may be utilized. The project was informed of the problem early through an issue report but has not responded yet.
AnalysisAI
Heap-based buffer overflow in LLVM llvm-project through version 22.1.6 allows a local low-privilege attacker to crash affected LLVM tooling by supplying a crafted bitcode file that triggers an out-of-bounds heap write in the GCRelocateInst::getBasePtr function within the Bitcode File Handler component. The LLVM project was notified via a GitHub issue report but has not yet responded or released a patch. A proof-of-concept exploit has been publicly disclosed, and no active exploitation is confirmed in CISA KEV.
Technical ContextAI
LLVM bitcode is a compact binary serialization of LLVM Intermediate Representation (IR), used extensively in link-time optimization (LTO), cross-platform compilation, and JIT frameworks. The affected function GCRelocateInst::getBasePtr resides in llvm/lib/IR/IntrinsicInst.cpp and handles GC (garbage collector) relocation intrinsics embedded in bitcode files. CWE-122 (Heap-based Buffer Overflow) describes the root cause: when parsing a specially crafted bitcode file, the function writes past the boundary of a heap-allocated buffer, potentially corrupting adjacent heap metadata or data. The CPE cpe:2.3:a:llvm:llvm-project:*:*:*:*:*:*:*:* confirms the affected software is the upstream llvm-project repository across all platforms, through version 22.1.6.
RemediationAI
No vendor-released patch has been identified at time of analysis, as the LLVM project has not yet responded to the coordinated disclosure reported via GitHub issue https://github.com/llvm/llvm-project/issues/199191. Organizations should monitor this issue tracker and upgrade as soon as a patched release is available. As a compensating control, restrict build pipelines so that only trusted, internally generated bitcode files are processed by LLVM tools such as llc or opt - do not allow externally sourced or user-submitted .bc files to be fed to the bitcode handler without prior sandboxing. Run LLVM build tools inside isolated containers or with syscall filtering (e.g., seccomp) so that a heap crash cannot cascade to other processes; the trade-off is added operational complexity in CI/CD environments. Restricting which local users can invoke LLVM bitcode processing tools reduces the pool of potential attackers, though this may impact developer workflows.
More in Llvm Project
View allSame weakness CWE-122 – Heap-based Buffer Overflow
View allSame technique Buffer Overflow
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External POC / Exploit Code
Leaving vuln.today