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NVD / CVE Program· CNA tenable

CVE-2021-20151: Trendnet AC2600 TEW-827DRU version 2.08B01 contains a flaw in the session management for the device.

Noroxi assessment

Priority: Plan (action score 40/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 1.6% (FIRST EPSS); higher than 76.8% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to the record, no fixed version is available yet.

Add it to your regular patch cycle. Update when a fix is released; follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Trendnet AC2600 TEW-827DRU version 2.08B01 contains a flaw in the session management for the device. The router's management software manages web sessions based on IP address rather than verifying client cookies/session tokens/etc. This allows an attacker (whether from a different computer, different web browser on the same machine, etc.) to take over an existing session. This does require the attacker to be able to spoof or take over original IP address of the original user's session.

CriticalCVSS 10.0 · v3.1—No exploit No fix recorded
Published
Dec 30, 2021
Updated
Jun 16, 2026
EPSS
1.6% · 76th percentile

Report tools

JSON

Action score

40

Plan

Add it to your regular patch cycle.

CVSS
40 / 40 · 10.0 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 1.6%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2021-20151

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
trendnettew-827dru firmware
trendnettew-827dru

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • trendnet tew-827dru firmware2.08b01

Versions reported by the vendor

Affected version ranges reported by the assigning authority (tenable). Independent of NVD's CPE analysis and usually ahead of it.

  • n/a Trendnet AC2600 TEW-827DRU

    • 2.08B01affected

Same product

trendnet: all records

Other highest-scoring records for the same primary product.

  • CVE-2021-20158Trendnet AC2600 TEW-827DRU version 2.08B01 contains an authentication bypass vulnerability.
    42Plan
  • CVE-2019-13278TRENDnet TEW-827DRU with firmware up to and including 2.04B03 contains multiple command injections when processing user input for the setup
    42Plan
  • CVE-2024-28354There is a command injection vulnerability in the TRENDnet TEW-827DRU router with firmware version 2.10B01.
    41Plan

Published before and after this one in the same product

  • ← EarlierCVE-2021-20149Dec 30, 2021 · Trendnet AC2600 TEW-827DRU version 2.08B01 does not have sufficient access controls for the WAN interface.
    39Monitor
  • ← EarlierCVE-2021-20150Dec 30, 2021 · Trendnet AC2600 TEW-827DRU version 2.08B01 improperly discloses information via redirection from the setup wizard.
    33Monitor
  • Later →CVE-2021-20152Dec 30, 2021 · Trendnet AC2600 TEW-827DRU version 2.08B01 lacks proper authentication to the bittorrent functionality.
    26Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted

Impact can extend beyond the vulnerable component (scope changes).

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Changed
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-384 · Session Fixation

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records