{"id":"CVE-2026-2703","aliases":["EUVD-2026-7426","GHSA-pf2p-f275-6cmx"],"status":"published","title":"xlnt-community xlnt Encrypted XLSX File base64.cpp decode_base64 off-by-one","description":"A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt::detail::decode_base64 of the file source/detail/cryptography/base64.cpp of the component Encrypted XLSX File Parser. Executing a manipulation can lead to off-by-one. The attack requires local access. The exploit has been made available to the public and could be used for attacks. This patch is called f2d7bf494e5c52706843cf7eb9892821bffb0734. Applying a patch is advised to resolve this issue.","severity":{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00236,"percentile":0.14648,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-189","CWE-193"],"published":"2026-02-19T04:02:10Z","modified":"2026-10-28T11:09:57Z","products":[{"vendor":"xlnt-community","product":"xlnt"}],"references":[{"url":"https://vuldb.com/?id.346649","tags":["vdb-entry","technical-description","Third Party Advisory","VDB Entry","advisory"]},{"url":"https://vuldb.com/?ctiid.346649","tags":["signature","permissions-required","Permissions Required","VDB Entry","report"]},{"url":"https://vuldb.com/?submit.754377","tags":["third-party-advisory","Third Party Advisory","VDB Entry","advisory"]},{"url":"https://github.com/xlnt-community/xlnt/issues/137","tags":["issue-tracking","Exploit","Issue Tracking","Vendor Advisory","report"]},{"url":"https://github.com/oneafter/0128/blob/main/xl1/repro","tags":["exploit","Exploit","evidence"]},{"url":"https://github.com/xlnt-community/xlnt/commit/f2d7bf494e5c52706843cf7eb9892821bffb0734","tags":["patch","Patch","fix"]},{"url":"https://github.com/xlnt-community/xlnt/","tags":["product","Product","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-2703","tags":["advisory"]},{"url":"https://github.com/xlnt-community/xlnt"},{"url":"https://github.com/advisories/GHSA-pf2p-f275-6cmx"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/2xxx/CVE-2026-2703.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-2703","title":"xlnt-community xlnt Encrypted XLSX File base64.cpp decode_base64 off-by-one","description":"A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt::detail::decode_base64 of the file source/detail/cryptography/base64.cpp of the component Encrypted XLSX File Parser. Executing a manipulation can lead to off-by-one. The attack requires local access. The exploit has been made available to the public and could be used for attacks. This patch is called f2d7bf494e5c52706843cf7eb9892821bffb0734. Applying a patch is advised to resolve this issue.","status":"published","published":"2026-02-19T04:02:10.794Z","modified":"2026-02-24T01:40:43.838Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium","assessor":"cna"},{"version":"3.1","score":3.3,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C","level":"low","assessor":"cna"},{"version":"3.0","score":3.3,"vector":"CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C","level":"low","assessor":"cna"},{"version":"2.0","score":1.7,"vector":"AV:L/AC:L/Au:S/C:N/I:N/A:P/E:POC/RL:OF/RC:C","assessor":"cna"}],"cwes":["CWE-193","CWE-189"],"updated_at":"2026-11-02T13:48:46.911326Z"}],"euvd":[{"id":"EUVD-2026-7426","description":"A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt::detail::decode_base64 of the file source/detail/cryptography/base64.cpp of the component Encrypted XLSX File Parser. Executing a manipulation can lead to off-by-one. The attack requires local access. The exploit has been made available to the public and could be used for attacks. This patch is called f2d7bf494e5c52706843cf7eb9892821bffb0734. Applying a patch is advised to resolve this issue.","status":"published","published":"2026-02-19T04:02:10Z","modified":"2026-02-24T01:40:43Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium"}],"updated_at":"2026-11-02T19:48:31.660571Z"}],"ghsa":[{"id":"GHSA-pf2p-f275-6cmx","title":"A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt:...","description":"A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt::detail::decode_base64 of the file source/detail/cryptography/base64.cpp of the component Encrypted XLSX File Parser. Executing a manipulation can lead to off-by-one. The attack requires local access. The exploit has been made available to the public and could be used for attacks. This patch is called f2d7bf494e5c52706843cf7eb9892821bffb0734. Applying a patch is advised to resolve this issue.","status":"published","published":"2026-02-19T18:31:51Z","modified":"2026-02-19T18:32:03Z","cvss":[{"version":"4.0","score":1.9,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"low"},{"version":"3.1","score":3.3,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"low"}],"updated_at":"2026-11-02T15:06:16.865747Z"}],"nvd":[{"id":"CVE-2026-2703","description":"A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt::detail::decode_base64 of the file source/detail/cryptography/base64.cpp of the component Encrypted XLSX File Parser. Executing a manipulation can lead to off-by-one. The attack requires local access. The exploit has been made available to the public and could be used for attacks. This patch is called f2d7bf494e5c52706843cf7eb9892821bffb0734. Applying a patch is advised to resolve this issue.","status":"published","published":"2026-02-19T07:17:49.477Z","modified":"2026-06-17T10:31:34.243Z","cvss":[{"version":"4.0","score":1.9,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"low","assessor":"secondary"},{"version":"3.1","score":3.3,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"low","assessor":"secondary"},{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"},{"version":"2.0","score":1.7,"vector":"AV:L/AC:L/Au:S/C:N/I:N/A:P","level":"low","assessor":"secondary"}],"cwes":["CWE-189","CWE-193"],"updated_at":"2026-11-02T14:12:06.274729Z"}],"osv":[{"id":"CVE-2026-2703","title":"xlnt-community xlnt Encrypted XLSX File base64.cpp decode_base64 off-by-one","description":"A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt::detail::decode_base64 of the file source/detail/cryptography/base64.cpp of the component Encrypted XLSX File Parser. Executing a manipulation can lead to off-by-one. The attack requires local access. The exploit has been made available to the public and could be used for attacks. This patch is called f2d7bf494e5c52706843cf7eb9892821bffb0734. Applying a patch is advised to resolve this issue.","status":"published","published":"2026-02-19T04:02:10.794Z","modified":"2026-10-28T11:09:57.912827484Z","cvss":[{"version":"4.0","score":1.9,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"low"}],"cwes":["CWE-189","CWE-193"],"updated_at":"2026-11-02T15:44:59.80315Z"}]}}