A vulnerability was found in libtiff due to multiple potential integer overflows in raw2tiff.c. This flaw allows remote attackers to cause a denial of service or possibly execute an arbitrary code via a crafted tiff image, which triggers a heap-based buffer overflow.

Dominic Scheirlinck of VendHQ reports:

Many software projects and vendors have implemented support for the “Proxy” request header in their respective CGI implementations and languages by creating the “HTTPPROXY” environmental variable based on the header value. When this variable is used (in many cases automatically by various HTTP client libraries) any outgoing requests generated in turn from the attackers original request can be redirected to an attacker controlled proxy. This allows attackers to view potentially sensitive information, reply with malformed data, or to hold connections open causing a potential denial of service.

The PHP web framework contains will automatically populate the HTTPPROXY environmental variable with a user supplied "Proxy" header.

Last updated 11 February 2025

BIRD Internet Routing Daemon 1.6.x through 1.6.7 and 2.x through 2.0.5 has a stack-based buffer overflow. The BGP daemon's support for RFC 8203 administrative shutdown communication messages included an incorrect logical expression when checking the validity of an input message. Sending a shutdown communication with a sufficient message length causes a four-byte overflow to occur while processing the message, where two of the overflow bytes are attacker-controlled and two are fixed.

libexpat could allow a remote attacker to obtain sensitive information, caused by improper handling of XML external entity (XXE) declarations by the XMLExternalEntityParserCreate function. By using a specially crafted XML content, a remote attacker could exploit this vulnerability to obtain sensitive information, and use this information to launch further attacks against the affected system.

.NET and Visual Studio Denial of Service Vulnerability

HTTP/2 Rapid reset attack The HTTP/2 protocol allows clients to indicate to the server that a previous stream should be canceled by sending a RSTSTREAM frame. The protocol does not require the client and server to coordinate the cancellation in any way, the client may do it unilaterally. The client may also assume that the cancellation will take effect immediately when the server receives the RSTSTREAM frame, before any other data from that TCP connection is processed.

Abuse of this feature is called a Rapid Reset attack because it relies on the ability for an endpoint to send a RSTSTREAM frame immediately after sending a request frame, which makes the other endpoint start working and then rapidly resets the request. The request is canceled, but leaves the HTTP/2 connection open.

The HTTP/2 Rapid Reset attack built on this capability is simple: The client opens a large number of streams at once as in the standard HTTP/2 attack, but rather than waiting for a response to each request stream from the server or proxy, the client cancels each request immediately.

The ability to reset streams immediately allows each connection to have an indefinite number of requests in flight. By explicitly canceling the requests, the attacker never exceeds the limit on the number of concurrent open streams. The number of in-flight requests is no longer dependent on the round-trip time (RTT), but only on the available network bandwidth.

In a typical HTTP/2 server implementation, the server will still have to do significant amounts of work for canceled requests, such as allocating new stream data structures, parsing the query and doing header decompression, and mapping the URL to a resource. For reverse proxy implementations, the request may be proxied to the backend server before the RSTSTREAM frame is processed. The client on the other hand paid almost no costs for sending the requests. This creates an exploitable cost asymmetry between the server and the client.

Multiple software artifacts implementing HTTP/2 are affected. This advisory was originally ingested from the swift-nio-http2 repo advisory and their original conent follows.

swift-nio-http2 specific advisory swift-nio-http2 is vulnerable to a denial-of-service vulnerability in which a malicious client can create and then reset a large number of HTTP/2 streams in a short period of time. This causes swift-nio-http2 to commit to a large amount of expensive work which it then throws away, including creating entirely new Channels to serve the traffic. This can easily overwhelm an EventLoop and prevent it from making forward progress.

swift-nio-http2 1.28 contains a remediation for this issue that applies reset counter using a sliding window. This constrains the number of stream resets that may occur in a given window of time. Clients violating this limit will have their connections torn down. This allows clients to continue to cancel streams for legitimate reasons, while constraining malicious actors.

A heap-based buffer overflow issue was discovered in ImageMagick's ImportMultiSpectralQuantum() function in MagickCore/quantum-import.c. An attacker could pass specially crafted file to convert, triggering an out-of-bounds read error, allowing an application to crash, resulting in a denial of service.

A use-after-free exists in drivers/tee/teeshm.c in the TEE subsystem in the Linux kernel through 5.15.11. This occurs because of a race condition in teeshmgetfromid during an attempt to free a shared memory object.

A remote stack overflow in the TIPC networking module. With FORTIFYSOURCE's stricter memcpy() bounds checking, this can be exploited to cause remote DOS via kernel panic on systems using TIPC. Prior to these bounds checks, and with a canary leak (or no CONFIGSTACKPROTECTOR), this can be exploited for RCE.

Reference: https://www.openwall.com/lists/oss-security/2022/02/10/1

A vulnerability was found in cgroupreleaseagentwrite in kernel/cgroup/cgroup-v1.c in the Linux kernel. In this flaw, under certain circumstances, the cgroups v1 releaseagent feature can be used to escalate privilege and bypass namespace isolation unexpectedly.

Upstream Commit:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=24f6008564183aa120d07c03d9289519c2fe02af

A flaw was found in unrestricted eBPF usage by the BPFBTFLOAD, leading to a possible out-of-bounds memory write in the Linux kernel’s BPF subsystem due to the way a user loads BTF. This flaw allows a local user to crash or escalate their privileges on the system.

Last updated 25 April 2025

A flaw in the Linux Kernel found. If unprivileged users can mount FUSE filesystems, then can trigger use after free (UAF) that reads of write() buffers, allowing theft of (partial) /etc/shadow hashes or any other data from filesystem.

FUSE allows the userspace filesystem to specify on FUSEOPEN whether the file should use the normal kernel pagecache for handling read()/write() or just send FUSEREAD/FUSEWRITE requests directly to the userspace filesystem (using the flag FOPENDIRECTIO in fuseopenout::openflags).

In FOPENDIRECTIO mode, fusefilewriteiter() calls fusedirectwriteiter(), which normally calls fusedirectio(), which then imports the write buffer with fusegetuserpages(), which uses iovitergetpages() to grab references to userspace pages instead of actually copying memory.

On the filesystem device side, these pages can then either be read to userspace (via fusedevread()), or splice()d over into a pipe using fusedevspliceread() as pipe buffers with &nostealpipebufops.

This is wrong because after fusedevdoread() unlocks the FUSE request, the userspace filesystem can mark the request as completed, causing write() to return. At that point, the write buffer may be reused for other purposes, and the userspace filesystem should no longer have access to it.

In kernel/bpf/verifier.c , there is a possible way to manipulate pointer arithmetic due to a logic error in the code. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.

In the Linux kernel through 5.15.2, hwatlutilsfwrpcwait in drivers/net/ethernet/aquantia/atlantic/hwatl/hwatlutils.c allows an attacker (who can introduce a crafted device) to trigger an out-of-bounds write via a crafted length value.

A double-free flaw was found in the Linux kernel in the emsusbstartxmit function. This flaw allows an attacker to create a memory leak and corrupt the underlying data structure by calling free more than once.

In checkstackwritefixedoff and related functions of verifier.c, there is a possible out of bounds read due to side channel information disclosure. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.

An out-of-bounds (OOB) memory read flaw was found in the Qualcomm IPC router protocol in the Linux kernel. A missing sanity check allows a local attacker to gain access to out-of-bounds memory, leading to a system crash or a leak of internal kernel information. The highest threat from this vulnerability is to system availability.

In htabmaplookupanddeletebatch of hashtab.c, there is a possible out of bounds write due to an integer overflow. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.

An out-of-bounds (OOB) memory write flaw was found in preallocelemsandfreelist in kernel/bpf/stackmap.c in the bpf iin the Linux kernel. In this flaw, the multiplication to calculate the size could lead to an integer overflow, and this could allow a local attacker, with a special user privilege to gain access to out-of-bounds memory leading to a system crash or a leak of internal kernel information.

Reference and upstream patch: https://github.com/torvalds/linux/commit/30e29a9a2bc6a4888335a6ede968b75cd329657a

A heap buffer overflow flaw was found in IPsec ESP transformation code in net/ipv4/esp4.c and net/ipv6/esp6.c. This flaw allows a local attacker with a normal user privilege to overwrite kernel heap objects and may cause a local privilege escalation threat.

A flaw buffer overflow in the Linux kernel TIPC protocol functionality was found in the way user uses protocol with encryption enabled. A local user could use this flaw to crash the system.

A flaw was found in the Linux kernels eBPF implementation. By default, accessing the eBPF verifier is only accessible to privileged users with CAPSYSADMIN. A local user with the ability to insert eBPF instructions can abuse a flaw in eBPF to corrupt memory. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

A flaw was found in kernel/bpf/verifier.c in BPF in the Linux kernel. An incorrect limit is enforced for pointer arithmetic operations which can be abused to perform out-of-bounds reads and writes in kernel memory, leading to local privilege escalation. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

A use-after-free exists in the Linux Kernel in tcnewtfilter that could allow a local attacker to gain privilege escalation. The exploit requires unprivileged user namespaces. We recommend upgrading past commit 04c2a47ffb13c29778e2a14e414ad4cb5a5db4b5

A flaw was found in the Linux kernels eBPF verification code. By default accessing the eBPF verifier is only accessible to privileged users with CAPSYSADMIN. A local user with the ability to insert eBPF instructions can use the eBPF verifier to abuse a spectre like flaw where they can infer all system memory.

A null pointer dereference flaw was found in openssl. A remote attacker, able to control the arguments of the GENERALNAMEcmp function, could cause the application, compiled with openssl to crash resulting in a denial of service. The highest threat from this vulnerability is to system availability.

A flaw was discovered in the cryptographic receive code in the Linux kernel's implementation of transparent interprocess communication. An attacker, with the ability to send TIPC messages to the target, can corrupt memory and escalate privileges on the target system.

Last updated 25 April 2025