{"id":"CVE-2026-64317","state":"PUBLISHED","title":"isofs: bound Rock Ridge symlink components to the SL record","description":"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.","publishedAt":"2026-07-25T08:49:47.067Z","updatedAt":"2026-10-19T20:38:23.435Z","severity":{"score":7.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"1015e1c4b2fadd9c09704e24738e46598778c869","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"36fe7d25dbc40da0c6b1dd4513a4f69ac6164eee","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"a22cb6bb54dc167047ea9e70d97dfbc2c15649e3","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"b736b12108fd116c41777628f5a333791604df26","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"6bf41db09ef935d76fcc84ccf213b42c18de95ee","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"b5699642640d6cff357638738c5293985cd5a53d","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"9830725078c8483c6831ec10222ae724806ea36b","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"5fa1d6a5ec2356d2107dead614437c66fa7138b1","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/isofs/rock.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.12","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.96","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.39","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.4","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/isofs/rock.c"]}],"references":["https://git.kernel.org/stable/c/1015e1c4b2fadd9c09704e24738e46598778c869","https://git.kernel.org/stable/c/36fe7d25dbc40da0c6b1dd4513a4f69ac6164eee","https://git.kernel.org/stable/c/a22cb6bb54dc167047ea9e70d97dfbc2c15649e3","https://git.kernel.org/stable/c/b736b12108fd116c41777628f5a333791604df26","https://git.kernel.org/stable/c/6bf41db09ef935d76fcc84ccf213b42c18de95ee","https://git.kernel.org/stable/c/b5699642640d6cff357638738c5293985cd5a53d","https://git.kernel.org/stable/c/9830725078c8483c6831ec10222ae724806ea36b","https://git.kernel.org/stable/c/5fa1d6a5ec2356d2107dead614437c66fa7138b1","https://cert-portal.siemens.com/productcert/html/ssa-019113.html","https://cert-portal.siemens.com/productcert/html/ssa-457936.html"],"weaknesses":["CWE-125"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/64xxx/CVE-2026-64317.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64317","state":"PUBLISHED","datePublished":"2026-07-25T08:49:47.067Z","dateUpdated":"2026-10-19T20:38:23.435Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T15:36:31.779Z"},"containers":{"cna":{"title":"isofs: bound Rock Ridge symlink components to the SL record","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."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"1015e1c4b2fadd9c09704e24738e46598778c869","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"36fe7d25dbc40da0c6b1dd4513a4f69ac6164eee","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"a22cb6bb54dc167047ea9e70d97dfbc2c15649e3","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"b736b12108fd116c41777628f5a333791604df26","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"6bf41db09ef935d76fcc84ccf213b42c18de95ee","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"b5699642640d6cff357638738c5293985cd5a53d","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"9830725078c8483c6831ec10222ae724806ea36b","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"5fa1d6a5ec2356d2107dead614437c66fa7138b1","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/isofs/rock.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.12","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.96","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.39","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.4","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/isofs/rock.c"]}],"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"}],"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."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T04:53:17.683Z"},"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"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIPLUS S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIPLUS S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-457936.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-10-15T01:23:35.529Z"},"x_adpType":"supplier"},{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-64317","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-10-16T15:38:57.230320Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-125","lang":"en","type":"CWE","description":"CWE-125 Out-of-bounds Read"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T20:38:23.435Z"}}]}}}