Description
libde265 is an open source implementation of the h.265 video codec. Versions prior to 1.0.19 have a heap buffer overflow (out-of-bounds READ) exists in `decoder_context::decode_slice_unit_WPP()` in `libde265/decctx.cc`. When decoding a WPP (Wavefront Parallel Processing) HEVC slice, `ctbAddrRS` is computed as `ctbRow * ctbsWidth` inside the entry-point loop. If the PPS/SPS headers are crafted so that this value exceeds `pps.CtbAddrRStoTS.size()`, the subsequent array access `pps.CtbAddrRStoTS[ctbAddrRS]` reads past the end of the allocated vector, triggering a heap-buffer-overflow confirmed by AddressSanitizer. Version 1.0.19 patches the issue.
References1
Metrics
- CVSS 4.0
-
6.9
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/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 - EPSS — exploit probability
- 0% percentile: 37 · as of 14 November 2026
- CWE
- CWE-125
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