CVE-2026-67298
FreeRDP versions 3.28.0 and earlier contain a heap buffer overflow in the server-side RAIL channel handler (rail_server_handle_messages() in
CVSS
7.5
High
EPSS
—
KEV
—
Exploit Today
—
0-100
Published: Aug 1, 2026 · Last modified: Aug 1, 2026 · CWE-191
Not enough EPSS history yet.
FreeRDP versions 3.28.0 and earlier contain a heap buffer overflow in the server-side RAIL channel handler (rail_server_handle_messages() in channels/rail/server/rail_main.c). When processing a RAIL PDU header, the code subtracts RAIL_PDU_HEADER_LENGTH from the peer-controlled orderLength field without first verifying orderLength is at least the header length. For orderLength values 0..3 this causes an unsigned integer underflow to a very large size, which bypasses the Stream_EnsureRemainingCapacity() capacity check (due to pointer arithmetic wraparound) and is then passed to WTSVirtualChannelRead(), resulting in an out-of-bounds heap write. A malicious or compromised RDP client can exploit this to corrupt the heap and crash the server. Fixed in FreeRDP 3.29.0.
- github.comhttps://github.com/FreeRDP/FreeRDP/commit/46848765f2a1134f8652f8760eefb5e85d64a9b8
- github.comhttps://github.com/FreeRDP/FreeRDP/commit/5370fb26fbf034ecd11d3026b6ad639b5fff493f
- github.comhttps://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qmvw-52ph-q5pv
- www.vulncheck.comhttps://www.vulncheck.com/advisories/freerdp-heap-buffer-overflow-via-rail-orderlength-underflow
CVECVSSEPSSKEVRExploitTitleMod.
CVE-2026-633625.9 MED72.2%
——22An unsigned integer underflow in the PubSub signature verification path
in open62541 may allow a remote attacker to cause a denial of service
via a crafted UDP packet.1dCVE-2026-133088.1 HIG43.8%
——13Autel MaxiCharger AC Elite Home WebSockets Integer Underflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Autel MaxiCharger AC Elite Home EV chargers. Authentication is not required to exploit this vulnerability.
The specific flaw exists within the handling of WebSocket messages related to the OCPP service. The issue results from the lack of proper validation of user-supplied data, which can result in an integer underflow before allocating a buffer. An attacker can leverage this vulnerability to execute code in the context of the device. Was ZDI-CAN-29113.2dCVE-2026-54345—31.6%
——9gopacket provides packet processing capabilities for Go. In version 1.6.0 and earlier, the Diameter AVP decoder computes an AVP data length by subtracting a fixed header size from an attacker-controlled AVP Length field, so a vendor-flagged AVP whose Length is smaller than the 12-byte header underflows the unsigned 32-bit value and drives an unbounded allocation of roughly 4 GiB, and two such messages in succession OOM-kill a collector, causing an unauthenticated remote denial of service. This issue is fixed in version 1.6.1.2dCVE-2026-424955.5 MED10.7%
——3[This CNA information record relates to multiple CVEs; the
text explains which aspects/vulnerabilities correspond to which CVE.]
The directory and Rock Ridge / SUSP walk in libfsimage's iso9660 driver
derives several lengths directly from attacker-controlled on-disk fields
without validating them:
* The directory loop itself assumes a good record length. This is
CVE-2026-42494.
* The calculation of the System Use area may underflow. This is
CVE-2026-42495.
* The Rock Ridge extension loop assumes a good (inner) record length.
This is CVE-2026-62423.
* The Rock Ridge NM record processing assumes a good entry length.
This is CVE-2026-62424.
* The Rock Ridge CE record processing assumes a good size and offset.
This is CVE-2026-62425.4dCVE-2026-54890—24.3%
——7Integer Underflow (Wrap or Wraparound) vulnerability in erlang otp erlang/otp (erts modules), erlang otp erts (erts modules) allows Forced Integer Overflow, Excessive Allocation. This vulnerability is associated with program files erts/emulator/beam/external.c, emulator/beam/external.c.
The BIT_BINARY_EXT tag (77) handler in the External Term Format (ETF) decoder accepts an encoding with both length and trailing-bits fields set to zero. The subsequent computation of the bitstring size underflows an unsigned integer, producing a value of roughly 2^64 that is then passed as a memory allocation size. The allocator aborts the entire node with a message such as "Cannot allocate 2305843009213693951 bytes of memory (of type binary)".
The crash is a VM-level abort, not an Erlang-level exception. It cannot be intercepted by supervision trees, by try/catch, or by passing the [safe] option to binary_to_term/2 (which only restricts atom creation and does not perform structural validation of binary encodings).
Any application that decodes ETF from untrusted sources via binary_to_term/1,2 or enif_binary_to_term() is exposed. The Erlang distribution protocol also decodes incoming terms through the same code path, but distribution is expected to run on trusted networks per the OTP Secure Coding Guidelines (DSG-011).
This issue affects OTP from OTP 27.0 before OTP 29.0.4, OTP 28.5.0.4 and OTP 27.3.4.15, corresponding to erts from 15.0 before 17.0.4, 16.4.0.4 and 15.2.7.11.2dCVE-2026-660337.5 HIG29.7%
——9libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2_cipher_crypt() function in src/openssl.c that allows a malicious SSH server to crash any connecting client by negotiating AES-GCM ciphers during handshake. Attackers can exploit the underflow in the expression computing blocksize minus aadlen minus authentication tag length to trigger an out-of-bounds read and a memcpy call with a near-SIZE_MAX length argument, causing immediate process crash before any authentication occurs.2d