How severe is CVE-2026-20405?

CVE-2026-20405 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-20405 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-20405?

CVE-2026-20405 primarily affects Mediatek Nr15. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-20405?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-20405 have an EU (EUVD) identifier?

Yes. CVE-2026-20405 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5143.

When was CVE-2026-20405 published?

CVE-2026-20405 was published on 2026-02-02 and last updated on 2026-06-17.

CVE-2026-20405

CVE-2026-20405 is a medium-severity vulnerability in Mediatek Nr15 with a CVSS 3.x base score of 6.5. 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-617.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (12th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-5143
Weakness: CWE-617
Affected product: Mediatek Nr15
Published: 2026-02-02
Last modified: 2026-06-17

Description

In Modem, there is a possible system crash due to a missing bounds check. This could lead to remote denial of service, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: MOLY01688495; Issue ID: MSV-4818.

Frequently asked questions

What is CVE-2026-20405?: In Modem, there is a possible system crash due to a missing bounds check. This could lead to remote denial of service, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: MOLY01688495; Issue ID: MSV-4818.
How severe is CVE-2026-20405?: CVE-2026-20405 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-20405 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-20405?: CVE-2026-20405 primarily affects Mediatek Nr15. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-20405?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-20405 have an EU (EUVD) identifier?: Yes. CVE-2026-20405 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-5143.
When was CVE-2026-20405 published?: CVE-2026-20405 was published on 2026-02-02 and last updated on 2026-06-17.

References

https://corp.mediatek.com/product-security-bulletin/February-2026

Affected products (4)

cpe:2.3:o:mediatek:nr15:-:*:*:*:*:*:*:*
cpe:2.3:o:mediatek:nr16:-:*:*:*:*:*:*:*
cpe:2.3:o:mediatek:nr17:-:*:*:*:*:*:*:*
cpe:2.3:o:mediatek:nr17r:-:*:*:*:*:*:*:*

More vulnerabilities in Mediatek Nr15

CVE-2024-20082 — Critical (CVSS 9.8): In Modem, there is a possible memory corruption due to a missing bounds check. This could lead to remote code execution…
CVE-2023-32874 — Critical (CVSS 9.8): In Modem IMS Stack, there is a possible out of bounds write due to a missing bounds check. This could lead to remote…
CVE-2023-20819 — Critical (CVSS 9.8): In CDMA PPP protocol, there is a possible out of bounds write due to a missing bounds check. This could lead to remote…
CVE-2022-21744 — Critical (CVSS 9.8): In Modem 2G RR, there is a possible out of bounds write due to a missing bounds check. This could lead to remote code…
CVE-2022-20083 — Critical (CVSS 9.8): In Modem 2G/3G CC, there is a possible out of bounds write due to a missing bounds check. This could lead to remote…
CVE-2025-20708 — High (CVSS 8.8): In Modem, there is a possible out of bounds write due to an incorrect bounds check. This could lead to remote…

All CVEs affecting Mediatek Nr15 →

Other CWE-617 (Reachable Assertion) vulnerabilities

CVE-2020-3615 — Critical (CVSS 9.8): Valid deauth/disassoc frames is dropped in case if RMF is enabled and some rouge peer keep on sending rogue…
CVE-2019-9795 — Critical (CVSS 9.8): A vulnerability where type-confusion in the IonMonkey just-in-time (JIT) compiler could potentially be used by…
CVE-2026-31739 — High (CVSS 8.8): In the Linux kernel, the following vulnerability has been resolved: crypto: tegra - Add missing CRYPTO_ALG_ASYNC The…
CVE-2020-12417 — High (CVSS 8.8): Due to confusion about ValueTags on JavaScript Objects, an object may pass through the type barrier, resulting in…
CVE-2020-6623 — High (CVSS 8.8): stb stb_truetype.h through 1.22 has an assertion failure in stbtt__cff_get_index.
CVE-2020-6619 — High (CVSS 8.8): stb stb_truetype.h through 1.22 has an assertion failure in stbtt__buf_seek.

Browse all CWE-617 (Reachable Assertion) vulnerabilities →