Security readout for executives and security teams
Plain-English summary
A memory-corruption flaw in one identified TOTOLINK A800R firmware version could let a remote, authenticated attacker disrupt the router or potentially take control. Public exploit material exists, increasing near-term risk, but the supplied sources do not confirm active exploitation or a vendor fix.
Executive priority
Treat confirmed affected devices as urgent, especially when management access crosses untrusted networks. Public exploit availability raises risk, while remediation status remains unclear. Reduce administrative exposure immediately and obtain vendor guidance or plan device replacement.
Technical view
CVE-2026-19847 is a stack-based buffer overflow in setWiFiWpsConfig within wps.so, reached through /cgi-bin/cstecgi.cgi. Manipulating the pin argument triggers the flaw. The CVSS 2.0 vector indicates network access, low complexity, and single authentication, with possible confidentiality, integrity, and availability impact.
Likely exposure
Exposure is limited to confirmed TOTOLINK A800R devices running 4.1.2cu.5137_B20200730. Risk is greatest where the affected management CGI is reachable by untrusted users or compromised credentials. Other models and firmware versions are not established as affected by this source bundle.
Exploitation context
A public exploit is referenced, so technically capable attackers may reproduce the issue. However, the CVE is not listed as KEV, and the supplied sources provide no evidence of active exploitation. The CVSS vector indicates authentication is required.
Researcher notes
The affected function, endpoint, argument, and exact firmware are identified, but the supplied evidence does not establish exploitation in the wild, reliable code execution, affected adjacent versions, or an official patch. Avoid expanding the affected range without vendor confirmation or controlled validation.
Mitigation direction
- Identify and prioritize A800R devices running the affected firmware.
- Restrict router management access to trusted administrative networks and users.
- Check TOTOLINK guidance for a corrected firmware or supported remediation.
- Replace or isolate affected devices if no vendor-supported correction is available.
- Review and rotate administrative credentials where compromise is suspected.
Validation and detection
- Confirm each device model and exact installed firmware version.
- Determine whether the management interface is reachable from untrusted networks.
- Review logs for unusual requests involving cstecgi.cgi or WPS configuration.
- Investigate unexplained router crashes, restarts, or configuration changes.
- Verify remediation against current TOTOLINK guidance before closing findings.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
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-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 lookupCWE-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 lookupCVE-2026-19847 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9 (2.0)
- Known Exploited
- No
- Published
Vector: AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR
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.
SSVC decision data
CVSS vector scores
4 official scoresWe 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.
AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR810VulDBCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R2.85.9VulDBCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R2.85.9VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P——VulDBVulnerability scoring details
Base CVSS 4.0 score
8.7HighVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
Base CVSS 3.1 score
8.8HighVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
Base CVSS 3.0 score
8.8HighVector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
Base CVSS 2.0 score
9CriticalVector: AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- Source timelineVulDB
Advisory disclosed
- Source timelineVulDB
VulDB entry created
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- Source timelineVulDB
VulDB entry last update
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- VDB-389983 | TOTOLINK A800R wps.so cstecgi.cgi setWiFiWpsConfig stack-based overflowCVE reference, VulDB · vdb-entry, technical-description
- VDB-389983 | CTI Indicators (IOB, IOC, IOA)CVE reference, VulDB · signature, permissions-required
- CVE-2026-19847 | CVE Analysis and ReportCVE reference, VulDB · third-party-advisory
- Submit #869457 | Totolink A800R V4.1.2cu.5137_B20200730 Buffer OverflowCVE reference, VulDB · third-party-advisory
- https://github.com/panda666-888/vuls/blob/main/totolink/a800r/setWiFiWpsConfig.mdCVE reference, VulDB · exploit
- https://www.totolink.net/CVE reference, VulDB · product
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Restriction of Operations within the Bounds of a Memory Buffer
Improper Restriction of Operations within the Bounds of a Memory Buffer represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Stack-based Buffer Overflow
Stack-based Buffer Overflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.