Description

A vulnerability was found in warmcat libwebsockets 4.5.0. Impacted is the function report_raw_cbor of the file lib/misc/lecp.c of the component LECP CBOR Recording. The manipulation results in out-of-bounds write. The attack can be launched remotely. The exploit has been made public and could be used. The patch is identified as 1d44554a1bb262db63ff4e240152a9deecd99054. It is best practice to apply a patch to resolve this issue.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.3",
  "pubDate": "2026-08-24T01:16:57.360Z",
  "pubdate": "2026-08-24T01:16:57.360Z",
  "executiveSummary": "An out-of-bounds write vulnerability has been identified in warmcat libwebsockets version 4.5.0, specifically within the report_raw_cbor function located in the lib/misc/lecp.c file of the LECP CBOR Recording component.\nThis vulnerability is classified as an out-of-bounds write issue that can be exploited remotely by an unauthenticated attacker over the network.\nThe manipulation of the CBOR parsing logic results in memory corruption, which poses severe risk implications, including potential remote code execution or application crashes affecting the stability and confidentiality of the host system.\nPublic exploits for this vulnerability are currently available, increasing the urgency for remediation.\nSuccessful exploitation requires the targeted system to process maliciously crafted CBOR input provided by the remote attacker via the vulnerable component.",
  "technicalDetails": "The vulnerability resides in the report_raw_cbor function within the lib/misc/lecp.c source file of the LECP CBOR Recording component in warmcat libwebsockets 4.5.0.\nThe root cause stems from insufficient bounds checking and memory management when handling raw CBOR data recording, leading directly to an out-of-bounds write condition.\nExploitation occurs when an application utilizing the affected libwebsockets version processes a maliciously structured remote CBOR input stream.\nAs the parser processes the crafted payload, the vulnerable report_raw_cbor function fails to correctly validate buffer boundaries, causing data to be written outside the allocated memory region.\nThe attack vector is fully remote, requiring no prior authentication or specialized privileges on the target system.\nDepending on the memory layout and heap architecture, the resulting out-of-bounds write payload behavior can overwrite adjacent memory structures, potentially allowing arbitrary code execution under the context of the running process or triggering a denial of service through application termination.\nThe issue is directly addressed by applying the official security patch identified by commit hash 1d44554a1bb262db63ff4e240152a9deecd99054."
}