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Fencer Vulns
medium 5.5

CVE-2026-6521 json

Loop with Unreachable Exit Condition ('Infinite Loop') in Wireshark

published 2026-04-30 6 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-26329

cvss
5.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 3%
public exploits
0
none known

Summary

OpenFlow v5 protocol dissector infinite loops in Wireshark 4.6.0 to 4.6.4 and 4.4.0 to 4.4.14 allows denial of service

Patch / fix

  • Wireshark Foundation Wireshark 4.4.15, 4.6.5
  • wireshark Debian 13 4.4.15-0+deb13u1
  • wireshark Debian 14 4.6.5-1

debian advisories DEBIAN-CVE-2026-6521

  • wireshark SLE Module for Desktop Applications 15 SP7, SLE Module for Basesystem 15 SP7 4.6.7-150700.21.11.1
  • wireshark SLES LTSS Extended Security 12 SP5 2.4.16-48.69.1

suse advisories SUSE-SU-2026:3501-1SUSE-SU-2026:2969-1

  • wireshark openSUSE Tumbleweed 4.6.5-1.1

opensuse advisories openSUSE-SU-2026:10686-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-6521 updated cvss 6.5

Wireshark: Wireshark: Denial of Service via OpenFlow v5 protocol dissector infinite loop

  • Red Hat Enterprise Linux 6 wireshark, wireshark-gnome Red Hat Enterprise Linux 7 wireshark, wireshark-gnome Red Hat Enterprise Linux 8 wireshark, wireshark-cli Red Hat Enterprise Linux 9 wireshark, wireshark-cli Red Hat Enterprise Linux 10 wireshark
    affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
6 mo ago

Exploit prediction

0.14% chance of exploitation in the next 30 days, higher than 3% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • gitlab.com https://gitlab.com/wireshark/wireshark/-/work_items/21182 referenced PoC, tagged "exploit" by a source, unverified
  • gitlab.com https://gitlab.com/wireshark/wireshark/-/work_items/21188 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Affected products

  • Wireshark Foundation Wireshark

Classification

Weakness
  • CWE-835 Loop with Unreachable Exit Condition

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.