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Wireshark disclosed CVE-2026-6533, a flaw in its dissection engine that can cause the application to crash or consume excessive CPU resources when processing malformed LZ77-compressed data. The issue was reported as an SMB2 LZ77 decompression bomb and can be triggered either by a crafted packet seen on the wire or by opening a malicious packet capture file, resulting in a denial-of-service condition for analysts using the tool.
The vulnerability affects Wireshark versions 4.6.0 through 4.6.4 and 4.4.9 through 4.4.14. Wireshark fixed the bug in versions 4.6.5 and 4.4.15, and credited Sharon Brizinov with the discovery. The project said no active exploits were known at the time of disclosure, but organizations that rely on Wireshark for packet analysis should update affected installations to the patched releases.
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Wireshark published security advisory wnpa-sec-2026-28 for CVE-2026-6533, describing an LZ77 decompression crash in the dissection engine that could be triggered by malformed packets or trace files and could also cause excessive CPU consumption. The advisory says the issue affects versions 4.6.0 through 4.6.4 and 4.4.9 through 4.4.14, was discovered by Sharon Brizinov, and was fixed in versions 4.6.5 and 4.4.15.
A GitLab issue titled "SMB2 LZ77 Decompression Bomb (crash/dos)" was opened as issue #21127, documenting the underlying problem later tied to the Wireshark vulnerability.
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Wireshark disclosed **CVE-2026-5407**, an infinite-loop denial-of-service flaw in its SMB2 protocol dissector that can cause the application to consume excessive CPU resources when processing a malformed network packet or a crafted packet capture file. The issue was documented in a GitLab report and later published by Wireshark as advisory `wnpa-sec-2026-11`. The vulnerability affects Wireshark versions **4.6.0 through 4.6.4** and **4.4.0 through 4.4.14**. Wireshark said the flaw was fixed in versions **4.6.5** and **4.4.15**, and reported that no exploits were known at the time of disclosure. Organizations that use Wireshark for packet analysis should update affected installations to the patched releases to prevent malformed SMB2 traffic or capture files from locking the tool into an infinite loop.
Aug 21, 2026
Wireshark disclosed a high-severity flaw in its Kerberos protocol dissector that can crash **Wireshark** or **TShark** when processing malformed traffic or packet captures. The bug, tracked as `CVE-2026-76924` and documented in advisory `wnpa-sec-2026-78`, stems from an out-of-bounds read while formatting a preview of a learned `EncryptionKey` from plaintext Kerberos credential data. Researchers reported that a crafted `EncKrbCredPart`, including traffic delivered over UDP/88, could trigger a heap-buffer-overflow even without a valid keytab, valid key, or successful decryption. The vendor said the issue affects Wireshark versions **4.6.0 through 4.6.7** and **4.4.0 through 4.4.17**, and it has been fixed in **4.6.8** and **4.4.18**. The root cause was that the dissector copied bounded key bytes into retained storage but still read four bytes from the original input buffer, allowing one- to three-byte keys to cause the crash; the fix reformats the preview from a zero-initialized retained buffer after the bounded copy. Wireshark said malformed packets injected onto a network or malicious packet capture files could trigger the vulnerability, and no active exploits are known.
Aug 21, 2026
Wireshark disclosed **CVE-2026-5653**, a heap-based buffer overflow in its DCP-ETSI protocol dissector that can crash the network protocol analyzer and cause a denial of service. The flaw affects Wireshark versions `4.6.0` through `4.6.4` and `4.4.0` through `4.4.14`, and was assigned **CWE-122** with a **CVSS v3.1 score of 5.5**. According to the advisory, an attacker could trigger the issue by injecting a malformed packet onto the network or by convincing a user to open a crafted packet capture file. Wireshark fixed the vulnerability in versions `4.6.5` and `4.4.15`; the issue was discovered by Alexandre de Oliveira, and the vendor said no active exploits were known at the time of disclosure.
Aug 21, 2026