CVE-2026-34877 | mbed TLS up to 2.19.0/3.6.5/4.0.0 memory corruption

VDB-354950 · CVE-2026-34877 · GCVE-0-2026-34877 MBED TLS UP TO 2.19.0/3.6.5/4.0.0 MEMORY CORRUPTION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 7.3 $0-$5k 0.76+ Summaryinfo A vulnerability categorized as critical has been discovered in mbed TLS up to 2.19.0/3.6.5/4.0.0. This affects an unknown part. Such manipulation leads to memory corruption. This vulnerability is referenced as CVE-2026-34877. It is possible to launch the attack remotely. No exploit is available. Detailsinfo A vulnerability was found in mbed TLS up to 2.19.0/3.6.5/4.0.0. It has been rated as critical. Affected by this issue is an unknown functionality. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes: An issue was discovered in Mbed TLS versions from 2.19.0 up to 3.6.5, Mbed TLS 4.0.0. Insufficient protection of serialized SSL context or session structures allows an attacker who can modify the serialized structures to induce memory corruption, leading to arbitrary code execution. This is caused by Incorrect Use of Privileged APIs. The advisory is available at mbed-tls.readthedocs.io. This vulnerability is handled as CVE-2026-34877 since 03/31/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 04/02/2026). There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product. Productinfo Name mbed TLS Version 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11 2.12 2.13 2.14 2.15 2.16 2.17 2.18 2.19.0 3.6.0 3.6.1 3.6.2 3.6.3 3.6.4 3.6.5 4.0 CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 7.3 VulDB Meta Temp Score: 7.3 VulDB Base Score: 7.3 VulDB Temp Score: 7.3 VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Memory corruption CWE: CWE-119 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: no mitigation known Status: 🔍 0-Day Time: 🔒 Timelineinfo 03/31/2026 CVE reserved 04/02/2026 +2 days Advisory disclosed 04/02/2026 +0 days VulDB entry created 04/02/2026 +0 days VulDB entry last update Sourcesinfo Advisory: mbed-tls.readthedocs.io Status: Not defined CVE: CVE-2026-34877 (🔒) GCVE (CVE): GCVE-0-2026-34877 GCVE (VulDB): GCVE-100-354950 Entryinfo Created: 04/02/2026 19:33 Changes: 04/02/2026 19:33 (51) Complete: 🔍 Cache ID: 99:5BE:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸