{"id":"CVE-2024-57877","state":"PUBLISHED","title":"arm64: ptrace: fix partial SETREGSET for NT_ARM_POE","description":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64: ptrace: fix partial SETREGSET for NT_ARM_POE\n\nCurrently poe_set() doesn't initialize the temporary 'ctrl' variable,\nand a SETREGSET call with a length of zero will leave this\nuninitialized. Consequently an arbitrary value will be written back to\ntarget->thread.por_el0, potentially leaking up to 64 bits of memory from\nthe kernel stack. The read is limited to a specific slot on the stack,\nand the issue does not provide a write mechanism.\n\nFix this by initializing the temporary value before copying the regset\nfrom userspace, as for other regsets (e.g. NT_PRSTATUS, NT_PRFPREG,\nNT_ARM_SYSTEM_CALL). In the case of a zero-length write, the existing\ncontents of POR_EL1 will be retained.\n\nBefore this patch:\n\n| # ./poe-test\n| Attempting to write NT_ARM_POE::por_el0 = 0x900d900d900d900d\n| SETREGSET(nt=0x40f, len=8) wrote 8 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d\n|\n| Attempting to write NT_ARM_POE (zero length)\n| SETREGSET(nt=0x40f, len=0) wrote 0 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0xffff8000839c3d50\n\nAfter this patch:\n\n| # ./poe-test\n| Attempting to write NT_ARM_POE::por_el0 = 0x900d900d900d900d\n| SETREGSET(nt=0x40f, len=8) wrote 8 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d\n|\n| Attempting to write NT_ARM_POE (zero length)\n| SETREGSET(nt=0x40f, len=0) wrote 0 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d","publishedAt":"2025-01-11T14:49:03.297Z","updatedAt":"2026-05-11T20:59:37.368Z","severity":{"score":6.1,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"17519819926211e6b2834e00e4554bec0daf22ac","status":"affected","lessThan":"4105dd76bc8ad6529d47157ef0565cb84ca6676c","versionType":"git"},{"version":"17519819926211e6b2834e00e4554bec0daf22ac","status":"affected","lessThan":"594bfc4947c4fcabba1318d8384c61a29a6b89fb","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kernel/ptrace.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.12","versionType":"semver"},{"version":"6.12.5","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kernel/ptrace.c"]}],"references":["https://git.kernel.org/stable/c/4105dd76bc8ad6529d47157ef0565cb84ca6676c","https://git.kernel.org/stable/c/594bfc4947c4fcabba1318d8384c61a29a6b89fb"],"weaknesses":["CWE-908"],"ingestedAt":"2026-10-29T20:08:12.933Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2024/57xxx/CVE-2024-57877.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-57877","state":"PUBLISHED","datePublished":"2025-01-11T14:49:03.297Z","dateUpdated":"2026-05-11T20:59:37.368Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-01-11T14:45:42.023Z"},"containers":{"cna":{"title":"arm64: ptrace: fix partial SETREGSET for NT_ARM_POE","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64: ptrace: fix partial SETREGSET for NT_ARM_POE\n\nCurrently poe_set() doesn't initialize the temporary 'ctrl' variable,\nand a SETREGSET call with a length of zero will leave this\nuninitialized. Consequently an arbitrary value will be written back to\ntarget->thread.por_el0, potentially leaking up to 64 bits of memory from\nthe kernel stack. The read is limited to a specific slot on the stack,\nand the issue does not provide a write mechanism.\n\nFix this by initializing the temporary value before copying the regset\nfrom userspace, as for other regsets (e.g. NT_PRSTATUS, NT_PRFPREG,\nNT_ARM_SYSTEM_CALL). In the case of a zero-length write, the existing\ncontents of POR_EL1 will be retained.\n\nBefore this patch:\n\n| # ./poe-test\n| Attempting to write NT_ARM_POE::por_el0 = 0x900d900d900d900d\n| SETREGSET(nt=0x40f, len=8) wrote 8 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d\n|\n| Attempting to write NT_ARM_POE (zero length)\n| SETREGSET(nt=0x40f, len=0) wrote 0 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0xffff8000839c3d50\n\nAfter this patch:\n\n| # ./poe-test\n| Attempting to write NT_ARM_POE::por_el0 = 0x900d900d900d900d\n| SETREGSET(nt=0x40f, len=8) wrote 8 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d\n|\n| Attempting to write NT_ARM_POE (zero length)\n| SETREGSET(nt=0x40f, len=0) wrote 0 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"17519819926211e6b2834e00e4554bec0daf22ac","status":"affected","lessThan":"4105dd76bc8ad6529d47157ef0565cb84ca6676c","versionType":"git"},{"version":"17519819926211e6b2834e00e4554bec0daf22ac","status":"affected","lessThan":"594bfc4947c4fcabba1318d8384c61a29a6b89fb","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kernel/ptrace.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.12","versionType":"semver"},{"version":"6.12.5","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kernel/ptrace.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/4105dd76bc8ad6529d47157ef0565cb84ca6676c"},{"url":"https://git.kernel.org/stable/c/594bfc4947c4fcabba1318d8384c61a29a6b89fb"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T20:59:37.368Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.12.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.13"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":6.1,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"LOW"}},{"other":{"type":"ssvc","content":{"id":"CVE-2024-57877","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T19:54:54.484107Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-908","lang":"en","type":"CWE","description":"CWE-908 Use of Uninitialized Resource"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T19:57:19.815Z"}}]}}}