# Arm Mbed TLS vulnerabilities Source: https://junglewise.ai/threats/technologies/mbed-tls Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats Updated: 9 November 2026, 03:07 UTC. Rebuilt every hour. Data: https://junglewise.ai/threats/technologies/mbed-tls.json License: CC BY 4.0 with a link back Junglewise Threat Intelligence has tracked 14 vulnerabilities in Arm Mbed TLS: 0 in the last 7 days and 1 in the last 90 days, 3 of them critical and 0 exploited in the wild. The most recent, CVE-2026-25832, was published on 14 September 2026. Nothing in the last four weeks, down from 1 vulnerability in the four before. ## Counts - Last 7 days: 0 - Last 30 days: 0 - Last 90 days: 1 - All time: 14 (3 critical, 0 exploited in the wild) ## About Arm Mbed TLS An open source, portable, easy to use, readable and flexible SSL library. ## Latest Arm Mbed TLS vulnerabilities - [CVE-2026-25832: Mbed TLS TLS 1.3 HelloRetryRequest group validation bypass](https://junglewise.ai/threats/cve-2026-25832-mbed-tls-tls-1-3-helloretryrequest-group-validation-bypass) (low, CVSS 3.7, published 14 Sep 2026) - [CVE-2026-34877: Mbed TLS memory corruption via insecure deserialization of SSL context](https://junglewise.ai/threats/cve-2026-34877-mbed-tls-memory-corruption-via-insecure-deserialization-of-ssl) (critical, CVSS 9.8, published 2 Apr 2026) - [CVE-2026-34876: Mbed TLS out-of-bounds read in mbedtls_ccm_finish](https://junglewise.ai/threats/cve-2026-34876-mbed-tls-out-of-bounds-read-in-mbedtls-ccm-finish) (high, CVSS 7.5, published 2 Apr 2026) - [CVE-2026-34873: Mbed TLS client impersonation in TLS 1.3 session resumption](https://junglewise.ai/threats/cve-2026-34873-mbed-tls-client-impersonation-in-tls-1-3-session-resumption) (critical, CVSS 9.1, published 1 Apr 2026) - [CVE-2025-66442: In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only…](https://junglewise.ai/threats/cve-2025-66442-in-mbed-tls-through-4-0-0-there-is-a-compiler-induced-timing-side) (medium, CVSS 5.1, published 1 Apr 2026) - [CVE-2026-34874: Mbed TLS NULL pointer dereference in X.509 distinguished name parsing](https://junglewise.ai/threats/cve-2026-34874-mbed-tls-null-pointer-dereference-in-x-509-distinguished-name) (high, CVSS 7.5, published 1 Apr 2026) - [CVE-2026-34871: Arm Mbed TLS Predictable Seed in PRNG on Linux](https://junglewise.ai/threats/cve-2026-34871-arm-mbed-tls-predictable-seed-in-prng-on-linux) (medium, CVSS 6.7, published 1 Apr 2026) - [CVE-2026-25835: Arm Mbed TLS and TF-PSA-Crypto PRNG state cloning vulnerability](https://junglewise.ai/threats/cve-2026-25835-arm-mbed-tls-and-tf-psa-crypto-prng-state-cloning-vulnerability) (high, CVSS 7.7, published 1 Apr 2026) - [CVE-2026-25833: Mbed TLS buffer underflow in x509_inet_pton_ipv6](https://junglewise.ai/threats/cve-2026-25833-mbed-tls-buffer-underflow-in-x509-inet-pton-ipv6) (high, CVSS 7.5, published 1 Apr 2026) - [CVE-2026-34875: Mbed TLS buffer overflow in FFDH public key export](https://junglewise.ai/threats/cve-2026-34875-mbed-tls-buffer-overflow-in-ffdh-public-key-export) (critical, CVSS 9.8, published 1 Apr 2026) - [CVE-2026-25834: Mbed TLS algorithm downgrade in TLS 1.2 client](https://junglewise.ai/threats/cve-2026-25834-mbed-tls-algorithm-downgrade-in-tls-1-2-client) (medium, CVSS 6.5, published 1 Apr 2026) - [CVE-2025-49087: Mbed TLS timing side-channel in block cipher decryption with PKCS#7 padding](https://junglewise.ai/threats/cve-2025-49087-mbed-tls-timing-side-channel-in-block-cipher-decryption-with-pkcs) (medium, CVSS 4, published 20 Jul 2025) - [CVE-2025-49601: Mbed TLS out-of-bounds read in mbedtls_lms_import_public_key](https://junglewise.ai/threats/cve-2025-49601-mbed-tls-out-of-bounds-read-in-mbedtls-lms-import-public-key) (medium, CVSS 4.8, published 4 Jul 2025) - [CVE-2025-49600: Mbed TLS signature bypass in LMS verification](https://junglewise.ai/threats/cve-2025-49600-mbed-tls-signature-bypass-in-lms-verification) (medium, CVSS 4.9, published 4 Jul 2025) ## Most severe Arm Mbed TLS vulnerabilities - [CVE-2026-34877: Mbed TLS memory corruption via insecure deserialization of SSL context](https://junglewise.ai/threats/cve-2026-34877-mbed-tls-memory-corruption-via-insecure-deserialization-of-ssl) (critical, CVSS 9.8, published 2 Apr 2026) - [CVE-2026-34875: Mbed TLS buffer overflow in FFDH public key export](https://junglewise.ai/threats/cve-2026-34875-mbed-tls-buffer-overflow-in-ffdh-public-key-export) (critical, CVSS 9.8, published 1 Apr 2026) - [CVE-2026-34873: Mbed TLS client impersonation in TLS 1.3 session resumption](https://junglewise.ai/threats/cve-2026-34873-mbed-tls-client-impersonation-in-tls-1-3-session-resumption) (critical, CVSS 9.1, published 1 Apr 2026) - [CVE-2026-25835: Arm Mbed TLS and TF-PSA-Crypto PRNG state cloning vulnerability](https://junglewise.ai/threats/cve-2026-25835-arm-mbed-tls-and-tf-psa-crypto-prng-state-cloning-vulnerability) (high, CVSS 7.7, published 1 Apr 2026) - [CVE-2026-34874: Mbed TLS NULL pointer dereference in X.509 distinguished name parsing](https://junglewise.ai/threats/cve-2026-34874-mbed-tls-null-pointer-dereference-in-x-509-distinguished-name) (high, CVSS 7.5, published 1 Apr 2026) - [CVE-2026-25833: Mbed TLS buffer underflow in x509_inet_pton_ipv6](https://junglewise.ai/threats/cve-2026-25833-mbed-tls-buffer-underflow-in-x509-inet-pton-ipv6) (high, CVSS 7.5, published 1 Apr 2026) - [CVE-2026-34876: Mbed TLS out-of-bounds read in mbedtls_ccm_finish](https://junglewise.ai/threats/cve-2026-34876-mbed-tls-out-of-bounds-read-in-mbedtls-ccm-finish) (high, CVSS 7.5, published 2 Apr 2026) - [CVE-2026-34871: Arm Mbed TLS Predictable Seed in PRNG on Linux](https://junglewise.ai/threats/cve-2026-34871-arm-mbed-tls-predictable-seed-in-prng-on-linux) (medium, CVSS 6.7, published 1 Apr 2026) - [CVE-2026-25834: Mbed TLS algorithm downgrade in TLS 1.2 client](https://junglewise.ai/threats/cve-2026-25834-mbed-tls-algorithm-downgrade-in-tls-1-2-client) (medium, CVSS 6.5, published 1 Apr 2026) - [CVE-2025-66442: In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only…](https://junglewise.ai/threats/cve-2025-66442-in-mbed-tls-through-4-0-0-there-is-a-compiler-induced-timing-side) (medium, CVSS 5.1, published 1 Apr 2026) ## Vulnerabilities per week Nothing in the last four weeks, down from 1 vulnerability in the four before. | Week of | Vulns | Critical | Exploited | | --- | --- | --- | --- | | 17 Aug 2026 | 0 | 0 | 0 | | 24 Aug 2026 | 0 | 0 | 0 | | 31 Aug 2026 | 0 | 0 | 0 | | 7 Sep 2026 | 0 | 0 | 0 | | 14 Sep 2026 | 1 | 0 | 0 | | 21 Sep 2026 | 0 | 0 | 0 | | 28 Sep 2026 | 0 | 0 | 0 | | 5 Oct 2026 | 0 | 0 | 0 | | 12 Oct 2026 | 0 | 0 | 0 | | 19 Oct 2026 | 0 | 0 | 0 | | 26 Oct 2026 | 0 | 0 | 0 | | 2 Nov 2026 | 0 | 0 | 0 | | 9 Nov 2026 | 0 | 0 | 0 | ## Other Arm technologies - [Arm 5th Gen GPU Architecture Kernel Driver](https://junglewise.ai/threats/technologies/5th-gen-gpu-architecture-kernel-driver): 11 vulnerabilities - [Arm Valhall GPU Kernel Driver](https://junglewise.ai/threats/technologies/valhall-gpu-kernel-driver): 11 vulnerabilities - [Arm Bifrost GPU Kernel Driver](https://junglewise.ai/threats/technologies/bifrost-gpu-kernel-driver): 6 vulnerabilities - [Arm Mali Graphics Processing Unit (GPU)](https://junglewise.ai/threats/technologies/mali-graphics-processing-unit-gpu): 6 vulnerabilities - [Arm Keil MDK-Middleware](https://junglewise.ai/threats/technologies/keil-mdk-middleware): 3 vulnerabilities ## Sources NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories. Rebuilt every hour. Cite as: Junglewise Threat Intelligence, "Arm Mbed TLS vulnerabilities", https://junglewise.ai/threats/technologies/mbed-tls, 9 November 2026.