{"id":"CVE-2026-64317","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nisofs: bound Rock Ridge symlink components to the SL record\n\nget_symlink_chunk() and the SL handling in\nparse_rock_ridge_inode_internal() walk the variable-length compo…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nisofs: bound Rock Ridge symlink components to the SL record\n\nget_symlink_chunk() and the SL handling in\nparse_rock_ridge_inode_internal() walk the variable-length compo…","severity":"high","cvss":7.1,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","cwe":["CWE-125"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 2.6.12.1, < 5.10.261","linux_kernel >= 5.11, < 5.15.212","linux_kernel >= 5.16, < 6.1.178","linux_kernel >= 6.2, < 6.6.145","linux_kernel >= 6.7, < 6.12.96","linux_kernel >= 6.13, < 6.18.39","linux_kernel >= 6.19, < 7.1.4","linux_kernel = 2.6.12"],"patched":["linux_kernel 7.1.4"],"published":"2026-07-25","updated":"2026-09-08","sourceUpdated":"2026-09-08T09:18:18.020","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64317","references":[{"url":"https://git.kernel.org/stable/c/1015e1c4b2fadd9c09704e24738e46598778c869","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/36fe7d25dbc40da0c6b1dd4513a4f69ac6164eee","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5fa1d6a5ec2356d2107dead614437c66fa7138b1","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6bf41db09ef935d76fcc84ccf213b42c18de95ee","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9830725078c8483c6831ec10222ae724806ea36b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a22cb6bb54dc167047ea9e70d97dfbc2c15649e3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b5699642640d6cff357638738c5293985cd5a53d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b736b12108fd116c41777628f5a333791604df26","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.00167,"epssPercentile":0.06361,"ingestedAt":"2026-07-27T06:16:50.426Z","slug":"CVE-2026-64317","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nisofs: bound Rock Ridge symlink components to the SL record\n\nget_symlink_chunk() and the SL handling in\nparse_rock_ridge_inode_internal() walk the variable-length components of\na Rock Ridge \"SL\" (symbolic link) record.  Each component is a two-byte\nheader (flags, len) followed by len bytes of text, so it occupies\nslp->len + 2 bytes.  Both loops read slp->len and advance to the next\ncomponent, and get_symlink_chunk() additionally does\nmemcpy(rpnt, slp->text, slp->len), but neither checks that the component\nlies within the SL record before dereferencing it.\n\nA crafted SL record whose component declares a len that runs past the\nrecord (rr->len) therefore triggers an out-of-bounds read of up to 255\nbytes.  When the record sits at the tail of its backing buffer - for\nexample a small kmalloc()ed continuation block reached through a CE\nrecord - the read crosses the allocation; get_symlink_chunk() then\ncopies the out-of-bounds bytes into the symlink body returned to user\nspace by readlink(), disclosing adjacent kernel memory.\n\nISO 9660 images are routinely mounted from untrusted removable media -\ndesktop environments auto-mount them (e.g. via udisks2) without\nCAP_SYS_ADMIN - so the record contents are attacker-controlled.\n\nReject any component that does not fit in the remaining record bytes\nbefore using it.  In get_symlink_chunk() return NULL, like the existing\noutput-buffer (plimit) checks, so a malformed record makes readlink()\nfail with -EIO rather than silently returning a truncated target; in\nparse_rock_ridge_inode_internal() stop the inode-size walk.\n\n## Affected\n\n- `linux_kernel >= 2.6.12.1, < 5.10.261`\n- `linux_kernel >= 5.11, < 5.15.212`\n- `linux_kernel >= 5.16, < 6.1.178`\n- `linux_kernel >= 6.2, < 6.6.145`\n- `linux_kernel >= 6.7, < 6.12.96`\n- `linux_kernel >= 6.13, < 6.18.39`\n- `linux_kernel >= 6.19, < 7.1.4`\n- `linux_kernel = 2.6.12`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 7.1.4`","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}