Junglewise Threat Intelligence

CVE-2026-9759: Wireshark ROHC protocol dissector NULL pointer dereference

CVE-2026-9759 · Severity: medium · CVSS 5.5 · Published 2026-05-27

Vendors: Wireshark Foundation.

Executive brief

Wireshark is a widely used network protocol analyzer for troubleshooting and security analysis. A vulnerability in its ROHC protocol component allows an attacker to crash the application by providing a specially crafted network capture file or injecting malicious traffic. This results in a denial of service, potentially disrupting network monitoring or forensic investigations.

Technical details

A vulnerability exists in the ROHC (Robust Header Compression) dissector due to improper handling of uncompressed profiles (profile 0) when large Context Identifiers (CIDs) are present. Specifically, when a packet ends exactly at the CID field, the dissector attempts to allocate zero bytes via wmem_alloc, which returns a NULL pointer. Subsequent memory copy operations (tvb_memcpy) attempt to write to this NULL pointer or use an underflowed length value (SIZE_MAX), resulting in a crash. Exploitation requires the attacker to provide a malformed packet trace file or inject a specific multi-packet sequence into a live capture to establish the necessary ROHC context. The issue is fixed in versions 4.6.6 and 4.4.16.

Affected products

  • Wireshark Foundation Wireshark 4.6.0 to 4.6.5, 4.4.0 to 4.4.15

Timeline

  • 2026-05-19: advisory: Wireshark security advisory wnpa-sec-2026-51 published
  • 2026-05-27: disclosed: CVE-2026-9759 published to NVD

References