CVE-2026-13539
CVE-2026-13539 is a high-severity vulnerability with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v2: 9.0
- CVSS v4: 7.4
- EPSS exploit prediction: 0% (37th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-119
- Published:
- Last modified:
Description
A vulnerability was identified in Wavlink WL-NU516U1-A M16U1_V240425. The impacted element is the function sub_407504 of the file /cgi-bin/wireless.cgi of the component POST Parameter Handler. Such manipulation of the argument Guest_ssid leads to stack-based buffer overflow. The attack can be executed remotely. The exploit is publicly available and might be used. It is suggested to upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.
Frequently asked questions
- What is CVE-2026-13539?
- A vulnerability was identified in Wavlink WL-NU516U1-A M16U1_V240425. The impacted element is the function sub_407504 of the file /cgi-bin/wireless.cgi of the component POST Parameter Handler. Such manipulation of the argument Guest_ssid leads to stack-based buffer overflow. The attack can be executed remotely. The exploit is publicly available and might be used. It is suggested to upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.
- How severe is CVE-2026-13539?
- CVE-2026-13539 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-13539 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-13539?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2026-13539 published?
- CVE-2026-13539 was published on 2026-06-29.
References
- https://dl.wavlink.com/firmware/RD/WINSTAR_NU516U1-WO-A-2026-06-22-5ccde97-mt7628-squashfs-sysupgrade.bin
- https://github.com/Svigo-o/Wavlink_vul/tree/main/wavlink-wl-nu516u1-wireless-guestwifi-guestssid-buffer-overflow
- https://vuldb.com/cve/CVE-2026-13539
- https://vuldb.com/submit/834024
- https://vuldb.com/vuln/374547
- https://vuldb.com/vuln/374547/cti
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