{ "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" } } } }