{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2025-21796", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-21796", "idYear": 2025, "status": "PUBLISHED", "publishedAt": "2025-02-27T02:18:32.191Z", "updatedAt": "2026-10-15T01:04:29.859Z", "importedAt": "2026-10-24T01:57:29.455Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "nfsd: clear acl_access/acl_default after releasing them", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: clear acl_access/acl_default after releasing them\n\nIf getting acl_default fails, acl_access and acl_default will be released\nsimultaneously. However, acl_access will still retain a pointer pointing\nto the released posix_acl, which will trigger a WARNING in\nnfs3svc_release_getacl like this:\n\n------------[ cut here ]------------\nrefcount_t: underflow; use-after-free.\nWARNING: CPU: 26 PID: 3199 at lib/refcount.c:28\nrefcount_warn_saturate+0xb5/0x170\nModules linked in:\nCPU: 26 UID: 0 PID: 3199 Comm: nfsd Not tainted\n6.12.0-rc6-00079-g04ae226af01f-dirty #8\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS\n1.16.1-2.fc37 04/01/2014\nRIP: 0010:refcount_warn_saturate+0xb5/0x170\nCode: cc cc 0f b6 1d b3 20 a5 03 80 fb 01 0f 87 65 48 d8 00 83 e3 01 75\ne4 48 c7 c7 c0 3b 9b 85 c6 05 97 20 a5 03 01 e8 fb 3e 30 ff <0f> 0b eb\ncd 0f b6 1d 8a3\nRSP: 0018:ffffc90008637cd8 EFLAGS: 00010282\nRAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff83904fde\nRDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88871ed36380\nRBP: ffff888158beeb40 R08: 0000000000000001 R09: fffff520010c6f56\nR10: ffffc90008637ab7 R11: 0000000000000001 R12: 0000000000000001\nR13: ffff888140e77400 R14: ffff888140e77408 R15: ffffffff858b42c0\nFS: 0000000000000000(0000) GS:ffff88871ed00000(0000)\nknlGS:0000000000000000\nCS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000562384d32158 CR3: 000000055cc6a000 CR4: 00000000000006f0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n \n ? refcount_warn_saturate+0xb5/0x170\n ? __warn+0xa5/0x140\n ? refcount_warn_saturate+0xb5/0x170\n ? report_bug+0x1b1/0x1e0\n ? handle_bug+0x53/0xa0\n ? exc_invalid_op+0x17/0x40\n ? asm_exc_invalid_op+0x1a/0x20\n ? tick_nohz_tick_stopped+0x1e/0x40\n ? refcount_warn_saturate+0xb5/0x170\n ? refcount_warn_saturate+0xb5/0x170\n nfs3svc_release_getacl+0xc9/0xe0\n svc_process_common+0x5db/0xb60\n ? __pfx_svc_process_common+0x10/0x10\n ? __rcu_read_unlock+0x69/0xa0\n ? __pfx_nfsd_dispatch+0x10/0x10\n ? svc_xprt_received+0xa1/0x120\n ? xdr_init_decode+0x11d/0x190\n svc_process+0x2a7/0x330\n svc_handle_xprt+0x69d/0x940\n svc_recv+0x180/0x2d0\n nfsd+0x168/0x200\n ? __pfx_nfsd+0x10/0x10\n kthread+0x1a2/0x1e0\n ? kthread+0xf4/0x1e0\n ? __pfx_kthread+0x10/0x10\n ret_from_fork+0x34/0x60\n ? __pfx_kthread+0x10/0x10\n ret_from_fork_asm+0x1a/0x30\n \nKernel panic - not syncing: kernel: panic_on_warn set ...\n\nClear acl_access/acl_default after posix_acl_release is called to prevent\nUAF from being triggered.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055", "status": "affected", "versionType": "git", "lessThan": "8a1737ae42c928384ab6447f6ee1a882510e85fa" }, { "version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055", "status": "affected", "versionType": "git", "lessThan": "6f7cfee1a316891890c505563aa54f3476db52fd" }, { "version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055", "status": "affected", "versionType": "git", "lessThan": "2e59b2b68782519560b3d6a41dd66a3d01a01cd3" }, { "version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055", "status": "affected", "versionType": "git", "lessThan": "55d947315fb5f67a35e4e1d3e01bb886b9c6decf" }, { "version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055", "status": "affected", "versionType": "git", "lessThan": "f8d871523142f7895f250a856f8c4a4181614510" }, { "version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055", "status": "affected", "versionType": "git", "lessThan": "1fd94884174bd20beb1773990fd3b1aa877688d9" }, { "version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055", "status": "affected", "versionType": "git", "lessThan": "7faf14a7b0366f153284db0ad3347c457ea70136" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "2.6.13", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "2.6.13" }, { "version": "5.10.235", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.179", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.129", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.79", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.16", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.13.4", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.13.*" }, { "version": "6.14", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }