{"id":"AZL-95892","summary":"CVE-2026-19548 affecting package binutils 2.41-13","details":"Multiple Use-After-Free vulnerabilities were found in the add_archive_element function in ld/ldmain.c of the GNU linker (ld), a component of binutils. The root cause is that plugin_maybe_claim() in ld/plugin.c frees the original BFD object via bfd_close/_bfd_delete_bfd when entry-\u003ethe_bfd-\u003emy_archive == NULL, but the caller retains both the original abfd parameter and a shallow copy (orig_input.the_bfd) as dangling pointers. These dangling pointers are subsequently dereferenced at three distinct locations in add_archive_element:\n\n1. Line ~1442: accessing abfd-\u003emy_archive via bfd_usrdata(abfd-\u003emy_archive)\n2. Line ~1493: multiple accesses to abfd and abfd-\u003emy_archive in a conditional check and bfd_get_filename call\n3. Line ~1525: dereferencing the shallow copy orig_input.the_bfd-\u003emy_archive in trace/verbose logging\n\nThe vulnerability is triggered when LTO plugins are active (link_info.lto_plugin_active is true) and the input object has abfd-\u003emy_archive == NULL, which is a valid state for standalone object files. Red Hat builds binutils with --enable-plugins and --enable-lto, confirming the vulnerable code path is compiled in and reachable.\n\nAn attacker who can supply a crafted object or archive file to a build process using LTO-enabled linking could exploit this flaw to cause a denial of service (linker crash via segmentation fault). Arbitrary code execution is theoretically possible through heap manipulation but is substantially mitigated by hardening measures including stack protector, FORTIFY_SOURCE, ASLR, and PIE.\n\nThe attack surface is limited to build-time environments — the linker is a development tool not exposed in production runtime. The most realistic exploitation scenario is a supply chain attack introducing a crafted object file as a build dependency in CI/CD pipelines or development environments.","modified":"2026-08-31T05:26:27Z","published":"2026-08-12T16:16:55Z","upstream":["CVE-2026-19548"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-19548"}],"affected":[{"package":{"name":"binutils","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/binutils"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"2.41-13"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-95892.json"}}],"schema_version":"1.9.0"}