A flaw was found in the math/big package of Go's standard library that causes a denial of service. Applications written in Go that use math/big via cryptographic packages, including crypto/rsa and crypto/x509, are vulnerable and can potentially cause panic via a crafted certificate chain. The highest threat from this vulnerability is to system availability.

A malicious HTTP/2 client which rapidly creates requests and immediately resets them can cause excessive server resource consumption. While the total number of requests is bounded by the http2.Server.MaxConcurrentStreams setting, resetting an in-progress request allows the attacker to create a new request while the existing one is still executing.

With the fix applied, HTTP/2 servers now bound the number of simultaneously executing handler goroutines to the stream concurrency limit (MaxConcurrentStreams). New requests arriving when at the limit (which can only happen after the client has reset an existing, in-flight request) will be queued until a handler exits. If the request queue grows too large, the server will terminate the connection.

This issue is also fixed in golang.org/x/net/http2 for users manually configuring HTTP/2.

The default stream concurrency limit is 250 streams (requests) per HTTP/2 connection. This value may be adjusted using the golang.org/x/net/http2 package; see the Server.MaxConcurrentStreams setting and the ConfigureServer function.

A closing HTTP/2 server connection could hang forever waiting for a clean shutdown that was preempted by a subsequent fatal error. This failure mode could be exploited to cause a denial of service.

References: https://go.dev/issue/54658 https://groups.google.com/g/golang-announce/c/x49AQzIVX-s/m/0tgO0pjiBQAJ

Upstream Commits: Master: https://github.com/golang/go/commit/29af494fca8a25d7d46276f6d4835c4dcd09e47d Branch.go1.18 : https://github.com/golang/go/commit/5bc9106458fc07851ac324a4157132a91b1f3479 Branch.go1.19 : https://github.com/golang/go/commit/9cfe4e258b1c9d4a04a42539c21c7bdb2e227824

A flaw was found in golang encoding/xml. When calling Decoder, Skip while parsing a deeply nested XML document, a panic can occur due to stack exhaustion and allows an attacker to impact system availability.

A flaw was found in the Go encoding/binary package. Certain invalid inputs to the ReadUvarint or the ReadVarint causes those functions to read an unlimited number of bytes from the ByteReader argument before returning an error. This flaw possibly leads to processing more input than expected. The highest threat from this vulnerability is to system availability.

A flaw was found Go's net/http package. Servers using ReverseProxy from net/http in the Go standard library are vulnerable to a data race that results in a denial of service. The highest threat from this vulnerability is to system availability.

A flaw was found in golang. Extraneous zero characters at the beginning of an IP address octet are not properly considered which could allow an attacker to bypass IP-based access controls. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Golang Go could allow a local authenticated attacker to gain elevated privileges on the system, caused by a flaw when a binary is run with the setuid/setgid bits. By sending a specially crafted request, an authenticated attacker could exploit this vulnerability to gain elevated privileges. to read or write contents of the registers.

As announced by Go upstream on 2019-10-17: Invalid DSA public keys can cause a panic in dsa.Verify. In particular, using crypto/x509.Verify on a crafted X.509 certificate chain can lead to a panic, even if the certificates don’t chain to a trusted root. The chain can be delivered via a crypto/tls connection to a client, or to a server that accepts and verifies client certificates. net/http clients can be made to crash by an HTTPS server, while net/http servers that accept client certificates will recover the panic and are unaffected.

Moreover, an application might crash invoking crypto/x509.(CertificateRequest) CheckSignature on an X.509 certificate request, parsing a golang.org/x/crypto/openpgp Entity, or during a golang.org/x/crypto/otr conversation. Finally, a golang.org/x/crypto/ssh client can panic due to a malformed host key, while a server could panic if either PublicKeyCallback accepts a malformed public key, or if IsUserAuthority accepts a certificate with a malformed public key.

Upstream bug: https://github.com/golang/go/issues/34960

An issue was discovered in Mbed TLS 2.18.0 through 2.28.x before 2.28.8 and 3.x before 3.6.0 and Mbed Crypto. The PSA Crypto API mishandles shared memory.

A flaw was found in the Go standard library packages before upstream versions 1.15 and 1.14.8. Both the net/http/cgi and net/http/fcgi packages use a default Content-Type response header value of "text/html", rather than "text/plain". This flaw allows an attacker to exploit this issue in applications using these packages by uploading crafted files, allowing a Cross-site Scripting attack (XSS). The highest threat from this vulnerability is to confidentiality and integrity.

Mbed TLS 2.x before 2.28.5 and 3.x before 3.5.0 has a Buffer Overflow.

An attacker can cause excessive memory growth in a Go server accepting HTTP/2 requests. HTTP/2 server connections contain a cache of HTTP header keys sent by the client. While the total number of entries in this cache is capped, an attacker sending very large keys can cause the server to allocate approximately 64 MiB per open connection.

Arbitrary code execution during build via line directives in cmd/go

An out of bounds read vulnerability was found in debug/macho of the Go standard library. When using the debug/macho standard library (stdlib) and malformed binaries are parsed using Open or OpenFat, it can cause golang to attempt to read outside of a slice (array) causing a panic when calling ImportedSymbols. An attacker can use this vulnerability to craft a file which causes an application using this library to crash resulting in a denial of service.

A flaw detected in golang: crypto/elliptic, in which P-224 keys as generated can return incorrect inputs, reducing the strength of the cryptography. The highest threat from this vulnerability is confidentiality and integrity.

Golang Go could allow a remote attacker to execute arbitrary code on the system, caused by a flaw when running "go get" on a malicious module. By sending a specially crafted request using linker flags, an attacker could exploit this vulnerability to execute arbitrary code on the system.

In ISC BIND9 versions BIND 9.11.14 -> 9.11.19, BIND 9.14.9 -> 9.14.12, BIND 9.16.0 -> 9.16.3, BIND Supported Preview Edition 9.11.14-S1 -> 9.11.19-S1: Unless a nameserver is providing authoritative service for one or more zones and at least one zone contains an empty non-terminal entry containing an asterisk ("") character, this defect cannot be encountered. A would-be attacker who is allowed to change zone content could theoretically introduce such a record in order to exploit this condition to cause denial of service, though we consider the use of this vector unlikely because any such attack would require a significant privilege level and be easily traceable.

A flaw was found in the Bind package, where the DNSSEC verification code for the EdDSA algorithm leaks memory when there is a signature length mismatch. By spoofing the target resolver with responses that have a malformed EdDSA signature, an attacker can trigger a small memory leak, resulting in crashing the program.

A flaw was found in the Bind package. By spoofing the target resolver with responses that have a malformed ECDSA signature, an attacker can trigger a small memory leak, resulting in crashing the program.

A flaw was found in bind. When flooding the target resolver with special queries, an attacker can significantly impair the resolver's performance, effectively denying legitimate clients access to the DNS resolution service.

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.

Last updated 25 April 2025

A NULL pointer dereference flaw was found in btrfsrmdevice function in fs/btrfs/volumes.c in Linux Kernel, where triggering the bug requires ‘CAPSYSADMIN’. This could allow a local attacker to crash the system or leak kernel internal information.

References: https://lore.kernel.org/linux-btrfs/CAFcO6XO5TC5sEo-C9JGC75JkNAzkOSSLA3a=bwQqXFFbRTZ7Gw@mail.gmail.com/T/#md4b850f33616b7364f86e6fed144abc925f3669c https://lore.kernel.org/linux-btrfs/20210806102415.304717-1-wqu@suse.com/T/#u

A flaw was found in the System Security Services Daemon (SSSD). The pampasskeychildreaddata() function within the PAM passkey responder fails to properly handle raw bytes received from a pipe. Because the data is treated as a NUL-terminated C string without explicit termination, it results in an out-of-bounds read when processed by functions like snprintf(). A local attacker could potentially trigger this vulnerability by initiating a crafted passkey authentication request, causing the SSSD PAM responder to crash, resulting in a local Denial of Service (DoS).

A flaw was found in SSSD. The sssnssprotocolparseaddr() function in the NSS responder (src/responder/nss/nssprotocol.c) extracts a 32-bit addrlen value from the client request but only validates that the body is at least 8 bytes, without checking that addrlen fits within the remaining packet body. This unvalidated length is passed through to tallocmemdup() in cachereqdatacreate(), which copies addrlen bytes from the small request buffer, causing a heap-buffer-overflow read. A local attacker can trigger this by connecting to the world-writable NSS responder socket (/var/lib/sss/pipes/nss) and sending a SSSNSSGETHOSTBYADDR (0x0053) request with a large addrlen value and a valid address family payload so that inetntop() succeeds. Successful exploitation crashes the sssdnss responder, causing a denial of service for NSS name resolution. Reported via PSIRTSUPT-20553 by BreachX Zero Day Labs.

A flaw was found in SSSD. The sssnssprotocolfillinitgr() function in the NSS responder (src/responder/nss/nssprotocolgrent.c) pre-allocates the reply packet for all group entries using ssspacketgrow() but does not shrink the packet when groups are skipped (non-POSIX, incomplete, or filtered groups). ssspacketgrow() uses tallocreallocsize(), which does not zero-fill newly allocated memory. The trailing unwritten bytes therefore contain uninitialized heap data from the sssdnss process and are transmitted to the client at the grown packet length. A local attacker can exploit this by sending SSSNSSINITGR (0x0026) requests to the world-writable NSS responder socket (/var/lib/sss/pipes/nss), receiving uninitialized heap content in the reply tail. Through heap grooming (for example, a preceding getpwnam query), the leak can disclose other users' cached directory records and process heap pointers. The leaked data is limited to the sssdnss heap (directory-level information); credentials reside in separate sssdpam and sssdbe processes. Reported via PSIRTSUPT-20553 by BreachX Zero Day Labs.

A flaw was found in SSSD. The extractauthtokv1() function in the PAM responder (src/responder/pam/pamsrvcmd.c) reads a 32-bit authtokenlength from the client request but does not validate it against the remaining buffer size before passing it to sssauthtoksetpassword(). When sssauthtoksetstring() processes the token, it accesses str[len-1] using the unvalidated length, resulting in a heap-buffer-overflow read. A local attacker can trigger this by connecting to the world-writable PAM responder socket (/var/lib/sss/pipes/pam) and sending a crafted protocol v1 authentication request with an oversized authtokenlength value. The stock PAM client uses protocol v3, so this is only reachable via raw socket access. Protocol v2 includes an equivalent bounds check (c+datasize > blen), which is missing from v1. Successful exploitation crashes the sssdpam responder, causing a denial of service for SSSD-mediated authentication. Reported via PSIRTSUPT-20553 by BreachX Zero Day Labs.

A flaw was found in sssd. When authenticating with a YubiKey, the SSSD PAM responder can crash due to a use-after-free vulnerability, where a memory pointer is incorrectly handled. A local attacker could exploit this flaw by manipulating smartcard or YubiKey contents, leading to a denial of service that disrupts authentication. This vulnerability also presents a potential for privilege escalation, although it is difficult to exploit.

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.