CVE-2026-55368
h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit 48b7ae12107fd2b118e4641da49599e9aac8edd8, H2O's access-l
CVSS
8.1
Alto
EPSS
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KEV
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Exploit Today
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0-100
Publicado: 4 nov 2026 · Última mod.: 4 nov 2026 · CWE-787
Sin historial EPSS suficiente todavía.
h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit 48b7ae12107fd2b118e4641da49599e9aac8edd8, H2O's access-log formatter could write past its log-line buffer when an affected custom access-log format was configured. The allocation errors affected %{error}x, %q when the query string was empty, and numeric elements whose temporary terminating NUL reached the end of the buffer. A matching request could crash the server, while the effect of the one-byte NUL overwrite beyond a crash was not established. This vulnerability is fixed with commit 48b7ae12107fd2b118e4641da49599e9aac8edd8.
CVECVSSEPSSKEVRExplotTítuloVis.
CVE-2026-77372——
———VeraCrypt provides disk encryption with strong security based on TrueCrypt. Prior to 1.26.30, the Unix, macOS, and FreeBSD serialization paths in src/Platform/Serializer.cpp and src/Volume/VolumePassword.cpp accept untrusted length and count values when deserializing data that can cross from the unprivileged GUI or CLI to the root CoreService helper. Serializer::DeserializeWString allocates floor(size / sizeof(wchar_t)) elements but reads size bytes, so a non-aligned size can overflow the heap allocation. VolumePassword::Deserialize accepts PasswordSize values larger than the fixed 128-byte PasswordBuffer, allowing downstream DataPtr() and Size() consumers such as the KDF to read beyond the buffer. DeserializeString, DeserializeWString, and the string and wide-string list readers also lack allocation and collection bounds, which can exhaust memory, and a zero-length DeserializeString can access an empty vector. Windows uses a different path, and the immediate CoreService pipe writer is the same-user parent process, so the documented exposure is a local defense-in-depth boundary rather than a remote attack. This issue is fixed in 1.26.30.4hCVE-2026-1221277.5 ALT—
———CESNET ipfixcol2 2.7.1 before 2.9.0 contains a heap-based buffer overflow in Lz4Decoder.cpp that allows unauthenticated network peers to write past heap buffers. Attackers can declare a small ring buffer_size followed by a large decompressed_size to write up to 65535 controlled bytes and crash the collector.6hCVE-2026-1137809.3 CRÍ—
———ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. From 5.5.5 until 5.5.6, 6.0.4, and 6.1.1, the esp_tee trap entry in esp_tee_vectors_plic.S and esp_tee_vectors_clic.S saves a caller-controlled register frame through the REE-supplied stack pointer before switching to the trusted TEE stack or validating the pointer. A local unprivileged REE application can direct this machine-mode write into TEE-exclusive memory on ESP32-C5, ESP32-C6, ESP32-C61, and ESP32-H2 devices, breaking the REE/TEE isolation boundary and potentially corrupting TEE control-flow data for code execution, denial of service, or system crashes. Both secure-service ecall and interrupt entry paths contain the vulnerable ordering. This issue is fixed in version 5.5.6 and is scheduled to be fixed in versions 6.0.4 and 6.1.1.8hCVE-2026-1219628.1 ALT—
———FreeRDP before 3.32.2 contains a heap buffer overflow in transport_default_read_pdu when handling partial Early User Authorization reads during PROTOCOL_HYBRID_EX CredSSP. A malicious RDP server can split the four-byte EUA result into short reads that advance the stream pointer beyond the 16 KiB allocation, causing an out-of-bounds write and client denial of service.8hCVE-2026-1219546.5 MED—
———FreeRDP before 3.32.2 has a heap out-of-bounds write in the planar codec because freerdp_bitmap_planar_context_reset commits new dimensions before buffer reallocation succeeds, and a failed ResetGraphics is only logged. A malicious RDP server can send an oversized ResetGraphics PDU, then a GFX PLANAR command, to corrupt client heap memory and crash the client.8hCVE-2026-1219529.8 CRÍ—
———FreeRDP before 3.32.2 has an out-of-bounds write in the proxy because rdp_read_bitmap_cache_v2_capability_set rejects only numCellCaches values above 5, yet the bitmap cache v2 cell array is later accessed at fixed indices 0 through 4. A client connecting to the proxy can declare fewer than five cell caches in its Confirm Active, causing heap corruption, heap data leakage to the backend, or a crash.8h