Security readout for executives and security teams
Plain-English summary
TP-Link Archer A7 routers running firmware Ver: 190726 have a critical flaw that can let an unauthenticated remote attacker run code as root. The issue is in DNS response handling, so compromise could affect confidentiality, integrity, and availability of the router and traffic depending on deployment.
Executive priority
Treat this as urgent for any confirmed affected router. The flaw can allow full router compromise without authentication, and routers often sit at trust boundaries. If affected devices exist, prioritize vendor-confirmed remediation or replacement.
Technical view
CVE-2020-10881 is a CWE-121 stack-based buffer overflow in TP-Link Archer A7 AC1750 firmware Ver: 190726. A crafted DNS response can overflow a fixed-length stack buffer and allow arbitrary code execution as root. CVSS 3.0 is 9.8 with network attack vector, low complexity, no privileges, and no user interaction.
Likely exposure
Exposure is limited by the provided sources to TP-Link Archer A7 AC1750 devices running firmware Ver: 190726. Organizations should prioritize branch, home-office, lab, and small-site inventories where consumer routers may be unmanaged or outside standard patch tracking.
Exploitation context
The sources state remote unauthenticated exploitation is possible, but the provided bundle does not show CISA KEV listing or confirmed active exploitation. Treat as high-risk because successful exploitation runs code as root on network infrastructure.
Researcher notes
Evidence identifies DNS response parsing as the vulnerable path and root as the execution context. The source bundle does not include exploit code, patch identifiers, or active exploitation evidence. Scope should not be extended beyond Archer A7 firmware Ver: 190726 without additional vendor data.
Mitigation direction
- Inventory TP-Link Archer A7 devices and record firmware versions.
- Check TP-Link support guidance for firmware addressing CVE-2020-10881.
- Upgrade or replace affected firmware when vendor guidance confirms remediation.
- Reduce reliance on affected routers until remediation is confirmed.
- Monitor affected networks for router instability or suspicious DNS-related behavior.
Validation and detection
- Confirm whether any Archer A7 device runs firmware Ver: 190726.
- Compare findings against the CVE and ZDI advisory scope.
- Verify remediation status through vendor firmware release notes or support guidance.
- Do not validate by sending crafted DNS messages in production.
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-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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2020-10881 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
- 9.8 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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.
CVSS vector scores
1 official scoreWe 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.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
9.8CriticalVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://www.zerodayinitiative.com/advisories/ZDI-20-333/CVE reference · x_refsource_MISC
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.
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.