CVE-2026-12339

MEDIUMPre-NVD 6.96.9—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.9 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 76% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 3 sources updated this week
6.9EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.9Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

A Zip Slip vulnerability in the WebUI ISP Upgrade functionality allows arbitrary file write via a crafted archive containing directory traversal sequences. An authenticated administrator may overwrite arbitrary files on the system.Successful exploitation may allow arbitrary file to overwrite on the underlying system, affecting system integrity and availability.

CVSS v3
6.9
EG Score
6.9(medium)
EG Risk
31(Track)
EG Risk 31/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity69% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
24%
KEV
Not listed

Published

August 10, 2026

Last Modified

August 18, 2026

Advisory Details (4)

Auto-updated Aug 10, 2026
No patch confirmed yet.
generic

Security Advisory: Authenticated Arbitrary File Write vulnerability in multiple devices (CVE-2026-12339) | TP-Link

https://www.tp-link.com/en/support/faq/5237/
generic

Download for Archer MR200 | TP-Link

https://www.tp-link.com/en/support/download/archer-mr200/v7/#Firmware
generic

Download for Archer MR600 | TP-Link

https://www.tp-link.com/en/support/download/archer-mr600/v2/#Firmware
generic

Download for TL-MR6400 | TP-Link

https://www.tp-link.com/en/support/download/tl-mr6400/v5.30/#Firmware

Vendor Advisories for CVE-2026-12339(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 19× in last 7d / 32× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-20 22:55 UTCEPSS rescore
  2. 2026-08-20 15:40 UTCEG score recompute
  3. 2026-08-20 15:40 UTCGHSA enrichment
  4. 2026-08-19 17:03 UTCEPSS rescore
  5. 2026-08-19 15:37 UTCGHSA enrichment
  6. 2026-08-18 15:33 UTCEG score recompute
  7. 2026-08-18 15:33 UTCGHSA enrichment
  8. 2026-08-18 13:48 UTCEPSS rescore
  9. 2026-08-17 15:58 UTCEG score recompute
  10. 2026-08-17 15:58 UTCGHSA enrichment
  11. 2026-08-16 15:54 UTCEG score recompute
  12. 2026-08-16 15:54 UTCGHSA enrichment
  13. 2026-08-16 14:56 UTCEPSS rescore
  14. 2026-08-16 02:14 UTCEPSS rescore
  15. 2026-08-15 15:51 UTCEG score recompute
  16. 2026-08-15 15:51 UTCGHSA enrichment
  17. 2026-08-15 01:30 UTCEPSS rescore
  18. 2026-08-14 15:47 UTCEG score recompute
  19. 2026-08-14 15:47 UTCGHSA enrichment
  20. 2026-08-13 22:00 UTCEPSS rescore
  21. 2026-08-13 15:43 UTCGHSA enrichment
  22. 2026-08-12 15:40 UTCEG score recompute
  23. 2026-08-12 15:40 UTCGHSA enrichment
  24. 2026-08-12 13:50 UTCEPSS rescore
  25. 2026-08-11 15:37 UTCEG score recompute
Show 7 more
  1. 2026-08-11 15:37 UTCGHSA enrichment
  2. 2026-08-11 14:58 UTCEG score recompute
  3. 2026-08-11 14:58 UTCGHSA enrichment
  4. 2026-08-11 13:42 UTCEPSS rescore
  5. 2026-08-10 19:27 UTCEG score recompute
  6. 2026-08-10 18:35 UTCEG score recompute
  7. 2026-08-10 18:34 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-12339?
CVE-2026-12339 is a medium vulnerability published on August 10, 2026. A Zip Slip vulnerability in the WebUI ISP Upgrade functionality allows arbitrary file write via a crafted archive containing directory traversal sequences. An authenticated administrator may overwrite arbitrary files on the system.Successful exploitation may allow arbitrary file to overwrite on the…
When was CVE-2026-12339 disclosed?
CVE-2026-12339 was first published in the National Vulnerability Database on August 10, 2026, with the most recent update on August 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-12339 actively exploited?
CVE-2026-12339 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 76.2% of all scored CVEs.
What is the CVSS score of CVE-2026-12339?
CVE-2026-12339 has a CVSS v3 base score of 6.9 (NVD).
How do I remediate CVE-2026-12339?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-12339, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-12339

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