{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64317","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-19T15:36:31.779Z","datePublished":"2026-07-25T08:49:47.067Z","dateUpdated":"2026-08-17T04:53:17.683Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-17T04:53:17.683Z"},"descriptions":[{"lang":"en","value":"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 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."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","baseScore":7.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - An active unprivileged local user can use UDisks2 to mount an attacker-created ISO image and invoke readlink(); ISOFS is not directly mountable through an unprivileged user namespace.\nAC:L - The attacker fully controls the SL component length and CE continuation layout, reliably triggering the out-of-bounds read without a race or an uncontrollable condition.\nPR:L - Direct mounting requires CAP_SYS_ADMIN in the initial user namespace, but common UDisks2 policies permit an active ordinary desktop user to create a loop device and mount the image without administrator authentication.\nUI:N - The local attacker can mount the crafted image and read the symlink themselves, requiring no action by another user.\nS:U - The disclosure and possible crash occur within the host kernel's existing security authority and do not cross a virtualization or comparable scope boundary.\nC:H - Up to 255 bytes per malformed SL component are copied from beyond a controllably sized kernel allocation into readlink() output; repeated components or attempts can disclose kernel pointers, secrets, and substantial adjacent heap data.\nI:N - The flaw performs an out-of-bounds source read while all destination writes remain bounded to the symlink page, providing no kernel-memory overwrite or control-flow modification primitive.\nA:H - The out-of-bounds memcpy can cross into inaccessible or allocator-guarded memory and cause a kernel oops or panic, and a local attacker can trigger repeated allocations and reads."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/isofs/rock.c"],"versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"1015e1c4b2fadd9c09704e24738e46598778c869","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"36fe7d25dbc40da0c6b1dd4513a4f69ac6164eee","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"a22cb6bb54dc167047ea9e70d97dfbc2c15649e3","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"b736b12108fd116c41777628f5a333791604df26","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"6bf41db09ef935d76fcc84ccf213b42c18de95ee","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"b5699642640d6cff357638738c5293985cd5a53d","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"9830725078c8483c6831ec10222ae724806ea36b","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"5fa1d6a5ec2356d2107dead614437c66fa7138b1","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/isofs/rock.c"],"versions":[{"version":"2.6.12","status":"affected"},{"version":"0","lessThan":"2.6.12","status":"unaffected","versionType":"semver"},{"version":"5.10.261","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.212","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.178","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.145","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.96","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.39","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.1.4","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"5.10.261"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"5.15.212"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.1.178"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.12.96"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.18.39"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"7.1.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/1015e1c4b2fadd9c09704e24738e46598778c869"},{"url":"https://git.kernel.org/stable/c/36fe7d25dbc40da0c6b1dd4513a4f69ac6164eee"},{"url":"https://git.kernel.org/stable/c/a22cb6bb54dc167047ea9e70d97dfbc2c15649e3"},{"url":"https://git.kernel.org/stable/c/b736b12108fd116c41777628f5a333791604df26"},{"url":"https://git.kernel.org/stable/c/6bf41db09ef935d76fcc84ccf213b42c18de95ee"},{"url":"https://git.kernel.org/stable/c/b5699642640d6cff357638738c5293985cd5a53d"},{"url":"https://git.kernel.org/stable/c/9830725078c8483c6831ec10222ae724806ea36b"},{"url":"https://git.kernel.org/stable/c/5fa1d6a5ec2356d2107dead614437c66fa7138b1"}],"title":"isofs: bound Rock Ridge symlink components to the SL record","x_generator":{"engine":"bippy-1.2.0"}}}}