This is a vulnerability report sent to us through https://issues.redhat.com/browse/PSIRTSUPT-18741 and was created using the PoC auto-triage agents. It contains hints on the vulnerability extracted by the IA and the full report. ALWAYS review it before any action. Once working on this, don't forget to also update the JSM ticket.

An out-of-bounds write vulnerability was found in the BFD library's DLX ELF backend (bfd/elf32-dlx.c) in GNU binutils. The dlxrtypetohowto() function maps ELF relocation types to internal howto structures but fails to perform adequate bounds checking on attacker-controlled relocation type values (via ELF32RTYPE(rinfo)) before indexing into the dlxelfhowtotable[] array. The DLX relocation type number space is non-contiguous (basic types 0-6, extended types at 0x10000+), but the default case in the switch statement allows arbitrary index values to reach the array access.

A specially crafted ELF/DLX object file can trigger this out-of-bounds write when processed by any BFD-consuming tool (objdump, readelf, strip, ld, nm, objcopy). The vulnerability has been demonstrated to achieve arbitrary code execution via a File Stream Oriented Programming (FSOP) attack against glibc FILE structures (stderr), redirecting control flow to system().

Attack scenarios include CI/CD pipelines performing automated binary analysis, developer workstations running objdump/readelf on untrusted binaries, automated security scanning or malware analysis tools invoking binutils, and package build systems processing third-party code.

Note: This vulnerability is only exploitable when binutils is built with the DLX backend enabled (typically via --enable-targets=all). Manual verification of Red Hat package build configurations is required to confirm affected product scope.

GNU Wget through 1.25.0, fixed in commit 37a40fc, contains a heap buffer underread vulnerability in the cleanmetalinkstring() function within src/metalink.c that allows a malicious server to trigger memory corruption by serving a Metalink document containing a whitespace-only URL. Attackers can cause the function to decrement a pointer past the start of the buffer when processing an all-whitespace Metalink URL, potentially leading to abnormal program behavior.

A flaw was found in GDB's STABS debug format parser. The readmemberfunctions() function in gdb/stabsread.c contains a linked list removal bug in the code that separates destructor and non-destructor member functions of C++ classes. The bug causes the destructor entries to remain in the main function list while the list length counter is decremented, resulting in an out-of-bounds write when the function list is copied to its final allocated array. An attacker can craft an ELF binary with malicious .stab and .stabstr sections that triggers this out-of-bounds write when a user opens the file in GDB and performs any symbol-inspection operation such as setting a breakpoint. The inferior process does not need to be executed. Under controlled conditions, this was demonstrated to achieve execution of arbitrary commands within the GDB process.

A flaw was found in the GDB STABS debug format parser. The readmemberfunctions() function in gdb/stabsread.c processes C++ member function lists from STABS symbol data. When a class contains both destructor and non-destructor member functions, the code at lines 5086-5131 attempts to separate them into two lists. However, the linked list removal logic has a bug: the lastsublist tracking variable is updated to point to REMOVED destructor nodes instead of the previous retained node, and the continue path for non-destructor nodes does not update lastsublist at all. This causes destructor entries to remain in the sublist linked list while the length variable is decremented by hasdestructor. In the subsequent copy loop (lines 5163-5166), the allocated array has length elements but the loop iterates over all remaining sublist entries (more than length). The loop index i starts at length and decrements, going negative, causing writes before the allocated obstack array. The written data consists of struct fnfield members controlled by the attacker through crafted STABS strings. The obstack underflow can corrupt chunk metadata including function pointers, which are called on subsequent obstack operations, resulting in arbitrary code execution. The vulnerability triggers automatically when GDB expands partial symbol tables — any symbol-inspection command (break, ptype, info functions) on a binary containing crafted .stab/.stabstr sections is sufficient. The inferior process does not need to be executed.

Upstream: https://sourceware.org/git/binutils-gdb.git Affected: gdb/stabsread.c (readmemberfunctions, lines 5086-5166) Confirmed on: GDB 16.3-1, Debian trixie, x86-64, glibc 2.41 Reporter: JD Marsters (Bhut Red)

Arbitrary File Write vulnerability in Rapid7 InsightConnect Sed Plugin on Linux allows authenticated attackers to write attacker-controlled content to arbitrary file paths via the expression parameter.

OS Command Injection vulnerability in Rapid7 InsightConnect Sed Plugin on Linux allows authenticated attackers to execute arbitrary OS commands via the expression parameter due to insufficient input validation.

acl before version 2.4.0 contains a time-of-check to time-of-use (TOCTOU) race condition vulnerability that allows local attackers to escalate privileges by replacing a pathname component with a symbolic link between an lstat() check and subsequent symlink-following operations such as stat(), chown(), chmod(), aclgetfile(), and aclsetfile(). Attackers who control a pathname component can redirect file access control list operations to arbitrary files when getfacl or setfacl is invoked by a privileged process over an attacker-controlled path, resulting in local privilege escalation.

In GNU SASL before 2.2.3, DIGEST-MD5 has a NULL pointer dereference affecting both clients and servers, via a known token with no accompanying = character. This occurs in lib/digest-md5/getsubopt.c.

A flaw was found in gnutls. A remote attacker could exploit an issue in the Datagram Transport Layer Security (DTLS) packet reordering logic. The comparator function, responsible for ordering DTLS packets by sequence numbers, did not correctly handle packets with duplicate sequence numbers. This could lead to unstable packet ordering or undefined behavior, resulting in a denial of service.

Last updated 30 June 2026

A flaw was found in binutils. A heap-buffer-overflow vulnerability exists when processing a specially crafted XCOFF (Extended Common Object File Format) object file during linking. A local attacker could trick a user into processing this malicious file, which could lead to arbitrary code execution, allowing the attacker to run unauthorized commands, or cause a denial of service, making the system unavailable.

Heap-buffer-overflow WRITE in xcofflinkaddsymbols() in bfd/xcofflink.c. Triggered by malformed XCOFF object file during linking. Fixed upstream by Alan Modra.

Public reference: https://sourceware.org/bugzilla/showbug.cgi?id=34049 Affects binutils <= 2.46.

A flaw was found in GNU Emacs. This vulnerability, a memory corruption issue, occurs when Emacs processes specially crafted SVG (Scalable Vector Graphics) CSS (Cascading Style Sheets) data. A local user could exploit this by convincing a victim to open a malicious SVG file, which may lead to a denial of service (DoS) or potentially information disclosure.

Calling the ungetwc function on a FILE stream with wide characters encoded in a character set that has overlaps between its single byte and multi-byte character encodings, in the GNU C Library version 2.43 or earlier, may result in an attempt to read bytes before an allocated buffer, potentially resulting in unintentional disclosure of neighboring data in the heap, or a program crash.

iconv crash due to assertion failure with untrusted input

Calling gethostbyaddr or gethostbyaddrr with a configured nsswitch.conf that specifies the library's DNS backend in the GNU C Library version 2.34 to version 2.43 could, with a crafted response from the configured DNS server, result in a violation of the DNS specification that causes the application to treat a non-answer section of the DNS response as a valid answer.

A flaw was found in gnutls. This vulnerability occurs because gnutls performs case-sensitive comparisons of nameConstraints labels, specifically for dNSName (DNS) or rfc822Name (email) constraints within excludedSubtrees or permittedSubtrees. A remote attacker can exploit this by crafting a leaf certificate with casing differences in the Subject Alternative Name (SAN), leading to a policy bypass where a certificate that should be rejected is instead accepted. This could result in unauthorized access or information disclosure.

GNU Binutils thru 2.46 readelf contains a double free vulnerability when processing a crafted ELF binary with malformed relocation data. During GOT relocation handling, dumprelocations may return early without initializing the allrelocations array. As a result, processgotsectioncontents() may pass an uninitialized rsymbol pointer to free(), leading to a double free and terminating the program with SIGABRT. No evidence of exploitable memory corruption or code execution was observed; the impact is limited to denial of service. NOTE: this is disputed by third parties because the observed behavior occurred only in pre-release code and did not affect any tagged version.

GNU Binutils thru 2.46 readelf contains a null pointer dereference vulnerability when processing a crafted ELF binary with malformed header fields. During relocation processing, an invalid or null section pointer may be passed into displayrelocations(), resulting in a segmentation fault (SIGSEGV) and abrupt termination. No evidence of memory corruption beyond the null pointer dereference, nor any possibility of code execution, was observed.

A flaw was found in GNU Binutils. This vulnerability, a heap-based buffer overflow, specifically an out-of-bounds read, exists in the bfd linker component. An attacker could exploit this by convincing a user to process a specially crafted malicious XCOFF object file. Successful exploitation may lead to the disclosure of sensitive information or cause the application to crash, resulting in an application level denial of service.

A flaw was found in GNU Binutils. This heap-based buffer overflow vulnerability, specifically an out-of-bounds read in the bfd linker, allows an attacker to gain access to sensitive information. By convincing a user to process a specially crafted XCOFF object file, an attacker can trigger this flaw, potentially leading to information disclosure or an application level denial of service.

Last updated 8 June 2026

A flaw was found in gnutls. A remote, unauthenticated attacker can exploit this vulnerability by sending a specially crafted ClientHello message with an invalid Pre-Shared Key (PSK) binder value during the TLS handshake. This can lead to a NULL pointer dereference, causing the server to crash and resulting in a remote Denial of Service (DoS) condition.

Calling wordexp with WRDEREUSE in conjunction with WRDEAPPEND in the GNU C Library version 2.0 to version 2.42 may cause the interface to return uninitialized memory in the wewordv member, which on subsequent calls to wordfree may abort the process.

Calling getnetbyaddr or getnetbyaddrr with a configured nsswitch.conf that specifies the library's DNS backend for networks and queries for a zero-valued network in the GNU C Library version 2.0 to version 2.42 can leak stack contents to the configured DNS resolver.

Integer overflow in memalign leads to heap corruption

Stack-based buffer overflow in libtasn1 version: v4.20.0. The function fails to validate the size of input data resulting in a buffer overflow in asn1expendoctetstring.

A NULL pointer dereference in the src/path.c component of GNU Unrtf v0.21.10 allows attackers to cause a Denial of Service (DoS) via injecting a crafted payload into the searchpath parameter.

A divide-by-zero in the encryption/decryption routines of GNU Recutils v1.9 allows attackers to cause a Denial of Service (DoS) via inputting an empty value as a password.

A flaw was found in GNU Wget2. This vulnerability, a stack-based buffer overflow, occurs in the filename sanitization logic when processing attacker-controlled URL paths, particularly when filename restriction options are active. A remote attacker can exploit this by providing a specially crafted URL, which, upon user interaction with wget2, can lead to memory corruption. This can cause the application to crash and potentially allow for further malicious activities.