Is CVE-2026-5405 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-5405 being exploited in the wild.

How severe is CVE-2026-5405?

High severity, with a CVSS score of 7.8, published 1 May 2026.

Which products and versions are affected?

Wireshark Foundation Wireshark 4.6.0 to 4.6.4, 4.4.0 to 4.4.14.

Is there a fix for CVE-2026-5405?

A patch was published on 2026-05-26: Red Hat released security updates for RHEL 10 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-5405 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-5405?

Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-5405: Wireshark heap overflow in RDP dissector

CVE-2026-5405 · Severity: high · CVSS 7.8 · Published 2026-05-01

Wireshark, a widely used network protocol analyzer, is vulnerable to a flaw in its Remote Desktop Protocol (RDP) analysis component. An attacker can exploit this by sending a specially crafted network packet or tricking a user into opening a malicious capture file. This could result in the application crashing or potentially allow the attacker to execute unauthorized code on the system.

Quick answers

Is CVE-2026-5405 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-5405 being exploited in the wild.
How severe is CVE-2026-5405?: High severity, with a CVSS score of 7.8, published 1 May 2026.
Which products and versions are affected?: Wireshark Foundation Wireshark 4.6.0 to 4.6.4, 4.4.0 to 4.4.14.
Is there a fix for CVE-2026-5405?: A patch was published on 2026-05-26: Red Hat released security updates for RHEL 10 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-5405 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-5405?: Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A heap-based buffer overflow exists in the RDP dissector's ZGFX decompression logic, specifically within the rdp8_decompress_segment() function in epan/tvbuff_rdp.c. The vulnerability is caused by a lack of bounds checking on the uncompressed path when copying attacker-controlled data into a fixed 65,536-byte outputSegment buffer. An attacker can trigger this overflow by providing a ZGFX segment larger than the buffer size. This is reachable through the standard RDP dissection chain (TCP 3389) via the Microsoft::Windows::RDS::Graphics dynamic channel. Successful exploitation can lead to a crash (SIGSEGV) or arbitrary code execution. Patches are available in Wireshark versions 4.6.5 and 4.4.15.

Affected products

Wireshark Foundation Wireshark 4.6.0 to 4.6.4, 4.4.0 to 4.4.14

Timeline

2026-04-29: advisory: Wireshark published wnpa-sec-2026-17
2026-05-01: disclosed: NVD publication date
2026-05-26: patched: Red Hat released security updates for RHEL 10

References

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