Vulnerability record · CVE-2026-40614 · published 21 April 2026
CVE-2026-40614: Pjsip heap-based buffer overflow vulnerability
Pjsip · Pjsip
PJSIP is a free and open source multimedia communication library written in C. In 2.16 and earlier, there is a buffer overflow when decoding Opus audio frames due to insufficient buffer size validation in the Opus codec decode path. The FEC decode buffers (dec_frame[].buf) were allocated based on a PCM-derived formula: (sample_rate/1000) * 60 * channel_cnt * 2. At 8 kHz mono this yields only 960 bytes, but codec_parse() can output encoded frames up to MAX_ENCODED_PACKET_SIZE (1280) bytes via opus_repacketizer_out_range(). The three pj_memcpy() calls in codec_decode() copied input->size bytes without bounds checking, causing a heap buffer overflow.
Description
PJSIP is a free and open source multimedia communication library written in C. In 2.16 and earlier, there is a buffer overflow when decoding Opus audio frames due to insufficient buffer size validation in the Opus codec decode path. The FEC decode buffers (dec_frame[].buf) were allocated based on a PCM-derived formula: (sample_rate/1000) * 60 * channel_cnt * 2. At 8 kHz mono this yields only 960 bytes, but codec_parse() can output encoded frames up to MAX_ENCODED_PACKET_SIZE (1280) bytes via opus_repacketizer_out_range(). The three pj_memcpy() calls in codec_decode() copied input->size bytes without bounds checking, causing a heap buffer overflow.
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/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:
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-40614), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.