CVE-2023-33538 — TP-Link Multiple Routers Command Injection Vulnerability
TP-Link TL-WR940N V2/V4, TL-WR841N V8/V10, and TL-WR740N V1/V2 was discovered to contain a command injection vulnerability via the component /userRpm/WlanNetworkRpm .
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- Confirmed exploitation (CISA KEV)+35
- Public exploit/PoC (github)+6
- EPSS 41.6% (30-day exploitation probability)+15
- Technical severity (high)+6
- Automatable exploitation (SSVC)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
CISA required action CISA
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
US federal deadline: Jul 7, 2025 — passed 465 day(s) ago
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (TP-Link Systems Inc. Tl-wr740n Firmware, TP-Link Systems Inc. Tl-wr841n Firmware, TP-Link Systems Inc. Tl-wr940n Firmware).
- Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- EPSS ahead of 99% of scored CVEs: prioritize it in the patch queue.
- Search available logs for exploit probes matching the vulnerability class (injection), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| TP-Link Systems Inc. | Tl-wr740n Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| TP-Link Systems Inc. | Tl-wr841n Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| TP-Link Systems Inc. | Tl-wr940n Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 8.8 | CVSS 3.1 | High | 2.8 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
| 8.8 | CVSS 3.1 | High | 2.8 | 5.9 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database |
| 8.8 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
| 8.8 | CVSS 3.1 | High | — | — | CISA-ADP via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
CISA KEV details CISA
CISA lists a CVE once it has evidence of exploitation against real targets.
CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.
Public exploits, PoCs and detection templates
Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.
- Python Exploit for TP-Link TL-WR940N/TL-WR841N Command Injection Vulnerability ★ 1 Jun 22, 2025
- CVE-2023-33538 - TP-Link Command Injection Ruby module for Metasploit Framework ★ 1 Jun 23, 2025
- rediscovered tplink nday xp (CVE-2023-33538) ★ 0 Apr 19, 2026
Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.
EPSS over time FIRST
Oct 12, 2026 → Oct 14, 2026 · 3 reading(s) · max 41.61%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Look for parameters with command/query metacharacters and unexpected child processes of the service.
- Hunt retroactively in logs from before Jun 16, 2025 (KEV listing): exploitation may have started earlier.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · tp-link/tl-wr940n firmware, tp-link/tl-wr841n firmware, tp-link/tl-wr740n firmware
- Source status changed · Published → Analyzed
- Record published
- CVSS changed · 8.8
- Source status changed · → Published
- SSVC assessment updated
- Added to CISA KEV (detected)
- Record created in this database
- 2025
- Added to CISA KEV catalog
- 2023
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 3× References added · Oct 13, 2026 – Oct 13, 2026
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
9 on the record
- www.cisa.gov/known-exploited-vulnerabilities-catalog
- nvd.nist.gov/vuln/detail/CVE-2023-33538
- www.secpod.com/blog/cisa-issues-warning-on-active-exploitation-of-tp-link-vulnerabil
- github.com/a101e-IoTvul/iotvul/blob/main/tp-link/3/TL-WR940N_TL-WR841N_userRpm_W
- www.tp-link.com/us/support/faq/3562
- github.com/advisories/GHSA-49g9-8m2w-hfgg
- web.archive.org/web/20230609111043/https://github.com/a101e-IoTvul/iotvul/blob/main/t
- www.secpod.com/blog/cisa-issues-warning-on-active-exploitation-of-tp-link-vulnerabil
- www.tp-link.com/us/support/faq/3562/
Elsewhere on this site
Related CVEs (same products)
- Medium CVE-2026-9105 Authenticated Stack-Based Buffer Overflow in TP-Link TL-WR841N Web Interface Jun 29, 2026
- High CVE-2026-11409 OS Command Injection in IPv6 PPPoE Configuration in TP-Link TL-WR940N Jun 17, 2026
- High CVE-2026-11410 OS Command Injection in BigPond Cable (BPA) Configuration in TP-Link TL-WR940N Jun 17, 2026
- High CVE-2026-5039 Predictable Default Cryptographic Key Used for DES Encryption in TP-Link TL-WL841N Apr 23, 2026
- High CVE-2026-3622 Denial-of-Service Vulnerability in UPnP Component of TP Link's TL-WR841N Mar 26, 2026
- Medium CVE-2026-3227 Authenticated Command Injection on TP-Link TL-WR802N, TL-WR841N and TL-WR840N Mar 16, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2023-33538 is "TP-Link Multiple Routers Command Injection Vulnerability", rated High. It affects Tl-wr740n Firmware (TP-Link Systems Inc.); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 8.8 describes technical severity. EPSS 41.61% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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