Heap-based Buffer Overflow Affecting xz_utils package, versions [,5.8.3)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published7 Apr 2026
- disclosed2 Apr 2026
- creditchristos-spearbit
Introduced: 2 Apr 2026
NewCVE-2026-34743 (opens in a new tab)How to fix?
Upgrade xz_utils to version 5.8.3 or higher.
Overview
Affected versions of this package are vulnerable to Heap-based Buffer Overflow in the lzma_index_decoder() function when processing an empty index, followed by a call to lzma_index_append(). An attacker can cause a buffer overflow and disrupt service availability by providing a specially crafted input that triggers insufficient memory allocation.