LiveActive security incident?Get immediate response
CVE Record

CVE-2026-86296: D-Link DIR-822A udhcpcd serverpacket.c strcpy stack-based overflow

A vulnerability was determined in D-Link DIR-822A A_101. This vulnerability affects the function strcpy of the file udhcpcd/serverpacket.c of the component udhcpcd. This manipulation causes stack-based buffer overflow. The attack is possible to be carried out remotely. The exploit has been publicly disclosed and may be utilized.

CriticalCVSS 10Not KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysiscritical

Security readout for executives and security teams

Plain-English summary

A flaw in one identified D-Link DIR-822A firmware release allows remote, unauthenticated network input to overrun device memory. A successful attack could crash the router or potentially compromise its confidentiality, integrity, and availability. Because routers sit at a network boundary, disruption or compromise could materially affect connectivity and trust, although the supplied sources document no real-world incidents.

Executive priority

Treat this as an urgent identification and containment issue. Locate affected routers immediately and reduce untrusted exposure. If D-Link provides no supported fix, prioritize replacement at internet-edge or critical locations. Do not infer an incident solely from this CVE; investigate device instability or other anomalies separately.

Technical view

DIR-822A firmware A_101 contains a stack-based buffer overflow involving strcpy in udhcpcd/serverpacket.c, associated with CWE-119 and CWE-121. The record rates it CVSS 4.0 10.0 and remotely reachable without privileges or user interaction. Public disclosure is reported, but the bundle establishes neither a vendor patch nor observed attacks.

Likely exposure

Supplied evidence limits exposure to D-Link DIR-822A devices running firmware A_101. Risk is highest where affected devices process relevant traffic from untrusted networks. The bundle identifies no other models, firmware branches, deployment modes, or exact reachable interfaces, so organizations should not broaden the affected scope without vendor confirmation.

Exploitation context

Technical details and an exploit reference are public, making attempted use plausible. However, the CVE is not listed in KEV, and supplied sources do not confirm active exploitation. Public disclosure should therefore be treated as increased risk, not evidence that compromise has occurred.

Researcher notes

The record identifies unsafe strcpy use in udhcpcd/serverpacket.c and classifies it as improper memory bounds handling and stack overflow. A linked disclosure names TR-111 Option 125 parsing, but the bundle does not reproduce its technical evidence. No vendor advisory, fixed version, or exploitation telemetry is provided; independent scope and patch verification remain necessary.

Mitigation direction

  • Inventory all D-Link DIR-822A devices and identify those running firmware A_101.
  • Check D-Link guidance for patched firmware or another supported remediation.
  • Reduce affected devices' exposure to untrusted networks where operationally feasible.
  • If no supported fix exists, isolate or replace affected routers based on business criticality.
  • Increase monitoring for unexpected resets, outages, or configuration changes.

Validation and detection

  • Verify the hardware model and exact firmware version using trusted inventory or device records.
  • Confirm replacement firmware against official D-Link release information before deployment.
  • Recheck the CVE record and VulDB entry for affected-version or remediation updates.
  • Review monitoring for unexplained router crashes; instability alone does not prove exploitation.
  • Document affected locations, network exposure, remediation status, and remaining exceptions.
Prepared
Confidence
medium
Sources
6

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-119: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cwe · low confidence lookup

CWE-121: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2026-86296 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Critical
CVSS
10 (4.0)
Known Exploited
No
Published

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

4CVSS vectors
6Timeline events
1ADP providers
7Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: pocAutomatable: yesTechnical Impact: total

CVSS vector scores

4 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
10CVSS 4.0CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P——VulDB
10CVSS 3.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:R3.96VulDB
10CVSS 3.0CriticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:R3.96VulDB
10CVSS 2.0CriticalAV:N/AC:L/Au:N/C:C/I:C/A:C/E:POC/RL:ND/RC:UR1010VulDB

Vulnerability scoring details

Base CVSS 4.0 score

10Critical
CVSS 4.0 vector shape for CVE-2026-86296Attack VectorAttack ComplexityAttack RequirementsPrivileges RequiredUser InteractionVS ConfidentialityVS IntegrityVS AvailabilitySS ConfidentialitySS IntegritySS Availability

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Attack Requirements
NonePresent
Privileges Required
NoneLowHigh
User Interaction
NonePassiveActive
VS Confidentiality
HighLowNone
VS Integrity
HighLowNone
VS Availability
HighLowNone
SS Confidentiality
HighLowNone
SS Integrity
HighLowNone
SS Availability
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. Source timelineVulDB

    Advisory disclosed

  2. Source timelineVulDB

    VulDB entry created

  3. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  4. Source timelineVulDB

    VulDB entry last update

  5. CVE publishedCVE Program

    The CVE record was published.

  6. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
D-LinkDIR-822AA_101Listed
Weakness

CWE details

CWE-119CWE-121

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.