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Full vulnerability report · 2026
CVE-2026-76886High confidence

Heap-based Buffer Overflow in Wireshark

Wireshark Foundation · Wireshark

8.1HighCVSS 3.1
Recommended action
Within 7 days

High technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Mitigation available
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

1 package state
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · standard archivewiresharkUnder evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2026-76886 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitywireshark: Wireshark: Denial of Service via C12.22 protocol dissector crash
20 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • wireshark as a component of Red Hat Enterprise Linux 10
  • wireshark-cli as a component of Red Hat Enterprise Linux 10
  • wireshark-devel as a component of Red Hat Enterprise Linux 10
  • wireshark.src as a component of Red Hat Enterprise Linux 10
  • wireshark as a component of Red Hat Enterprise Linux 6
  • wireshark-devel as a component of Red Hat Enterprise Linux 6
  • wireshark-gnome as a component of Red Hat Enterprise Linux 6
  • wireshark.src as a component of Red Hat Enterprise Linux 6
  • wireshark as a component of Red Hat Enterprise Linux 7
  • wireshark-devel as a component of Red Hat Enterprise Linux 7
  • wireshark-gnome as a component of Red Hat Enterprise Linux 7
  • wireshark.src as a component of Red Hat Enterprise Linux 7
Summary
A flaw was found in Wireshark. An unauthenticated remote attacker could exploit a vulnerability in the C12.22 protocol dissector by sending specially crafted network traffic. This could lead to a crash of the application, resulting in a Denial of Service (DoS).
Remediation
Do not populate the C12.22 decryption table, and disable the c1222.decrypt preference if crypto verification is not required. Avoid opening untrusted capture files or capturing C12.22 (TCP/1153) traffic from untrusted networks. If the C12.22 dissector is unused, disable it in protocol preferences.
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-63142

No EUVD known-exploited evidence

C12.22 protocol dissector crash in 4.6.0 to 4.6.7 and 4.4.0 to 4.4.18 allows denial of service

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
8.1 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Mitigation available
01

What, why and how

C12.22 protocol dissector crash in 4.6.0 to 4.6.7 and 4.4.0 to 4.4.18 allows denial of service

What

C12.22 protocol dissector crash in 4.6.0 to 4.6.7 and 4.4.0 to 4.4.18 allows denial of service

Why

A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

What

C12.22 protocol dissector crash in 4.6.0 to 4.6.7 and 4.4.0 to 4.4.18 allows denial of service

Why

A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Reference recorded

A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.

Likely attack path
a network path → Heap-based Buffer Overflow → disrupt the affected service
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-122 ↗

CWE-122: Heap-based Buffer Overflow. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedDenial of serviceCWE-122Public exploit reference
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2026-63142Official EUVD mapping

C12.22 protocol dissector crash in 4.6.0 to 4.6.7 and 4.4.0 to 4.4.18 allows denial of service

Official EUVD record
BSI · German · WID-SEC-W-2026-2806Wireshark: Mehrere Schwachstellen ermöglichen Denial of Service

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Wireshark ausnutzen, um einen Denial of Service Angriff durchzuführen.

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Mitigation available
Affected
wireshark as a component of Red Hat Enterprise Linux 10; wireshark-cli as a component of Red Hat Enterprise Linux 10; wireshark-devel as a component of Red Hat Enterprise Linux 10; wireshark.src as a component of Red Hat Enterprise Linux 10; wireshark as a component of Red Hat Enterprise Linux 6; wireshark-devel as a component of Red Hat Enterprise Linux 6; wireshark-gnome as a component of Red Hat Enterprise Linux 6; wireshark.src as a component of Red Hat Enterprise Linux 6; wireshark as a component of Red Hat Enterprise Linux 7; wireshark-devel as a component of Red Hat Enterprise Linux 7; wireshark-gnome as a component of Red Hat Enterprise Linux 7; wireshark.src as a component of Red Hat Enterprise Linux 7; wireshark as a component of Red Hat Enterprise Linux 8; wireshark-cli as a component of Red Hat Enterprise Linux 8; wireshark-devel as a component of Red Hat Enterprise Linux 8; wireshark.src as a component of Red Hat Enterprise Linux 8; wireshark as a component of Red Hat Enterprise Linux 9; wireshark-cli as a component of Red Hat Enterprise Linux 9; wireshark-devel as a component of Red Hat Enterprise Linux 9; wireshark.src as a component of Red Hat Enterprise Linux 9
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
Apply the mitigation in the linked authoritative guidance while planning the vendor's permanent fix.
Workaround
Do not populate the C12.22 decryption table, and disable the c1222.decrypt preference if crypto verification is not required. Avoid opening untrusted capture files or capturing C12.22 (TCP/1153) traffic from untrusted networks. If the C12.22 dissector is unused, disable it in protocol preferences.
04

Evidence and provenance

Published 19 Aug 2026 · Last source change 20 Aug 2026, 15:01 UTC · CWE-122 · Heap-based Buffer Overflow

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-23
European sourceENISA EUVD · EUVD-2026-63142
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →
  1. Vendor guidanceAuthoritative vendor guidance changed from no authoritative guidance recorded to authoritative remediation link · mitigation, vendor advisory.
    Before
    no authoritative guidance recorded
    After
    authoritative remediation link · mitigation, vendor advisory
    cve@gitlab.com ↗
  2. Remediation statusRemediation status changed from Awaiting fix to Mitigation available.
    Before
    Awaiting fix
    After
    Mitigation available
    cve@gitlab.com ↗
  3. Public exploit evidencePublic exploit evidence changed from Public exploit reference to Public exploit reference.
    Before
    Public exploit reference
    After
    Public exploit reference
    cve@gitlab.com ↗
  4. Public exploit evidencePublic exploit evidence changed from Public exploit reference to Public exploit reference.
    Before
    Public exploit reference
    After
    Public exploit reference
    CVE.org ↗
  5. Public exploit evidencePublic exploit evidence changed from No public exploit to Public exploit reference.
    Before
    No public exploit
    After
    Public exploit reference
    134c704f-9b21-4f2e-91b3-4a467353bcc0 ↗
  6. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Mitigation reference recorded
ENISA EUVD · EUVD-2026-63142↗Vendor CSAF · Red Hat Product Security↗CISA Vulnrichment SSVC evidence↗CVE authority or vendor reference↗Public exploit reference↗Public exploit reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-76886 · cve.blacktree.nl