Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd28a1aab8312928…

MALICIOUS

PDF

82.7 KB Created: 2021-09-18 22:26:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: aeb8201fbd07619068171cad09b4d076 SHA-1: dc2fc30d91349ef41c9819eda0d85e5f11518dd5 SHA-256: fd28a1aab8312928a0109adf9fbd2e335e6180da2741d38a77c452f9f9372e1f
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised WordPress sites, suggesting a link farm designed to distribute malware. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates that the document likely provides instructions to bypass security measures for a password-protected archive, a common tactic to hide malicious payloads. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://crewmak.ru/uplcv?utm_term=samsung+frp+tool+crack PDF link annotation
    • http://noithatmyhome.com/img/files/10535415104.pdfIn PDF document text
    • http://gesgo.de/userfiles/file/rofesefomosom.pdfIn PDF document text
    • http://knshzj.com/CKEdit/upload/files/37469504925.pdfIn PDF document text
    • https://yourwebcenter.com/files/file/13034628029.pdfIn PDF document text
    • https://giriconsultancy.com/content_files/files/91353868827.pdfIn PDF document text
    • http://ever-pioneer.com/upload/files/sakikotatolo.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/4c0b5ea5fbee3d074d7d0c2628dc02f6/munem.pdfIn PDF document text
    • http://tjtvina.com/Upload/files/nenagitarigokadis.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1614553dec6ee9---78605396.pdfIn PDF document text
    • https://alpinashop.bg/files/gakeluwijelidawus.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/fudasagimogetu.pdfIn PDF document text
    • http://dorrstrechy.cz/UserFiles/File/66662830512.pdfIn PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/18317381619.pdfIn PDF document text
    • https://vyrukrc.lt/userfiles/file/vutoro.pdfIn PDF document text
    • http://sdes.in/uploads/21974681393.pdfIn PDF document text
    • https://duvanco.be/docs/files/feronabafozoditat.pdfIn PDF document text
    • http://nsfeed.com/_UploadFile/Images/file/gipafasujijebapumumawuxe.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16141206cc3e20---pixemukanupuremet.pdfIn PDF document text
    • https://eltechma.com/zdjecia/fck/file/zetifevetutilidosedef.pdfIn PDF document text
    • https://solidpractise.com/files/userfiles/file/9561616660.pdfIn PDF document text
    • https://irish-setter-zucht.info/ckfinder/userfiles/files/30303924344.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161352e38b751f---30040564855.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133a609eb642---21838045042.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC54 10864 bytes
SHA-256: 41540973250ae444c17788b7b63894523c4d0a8857aa20912d7fd86659f8c75e
font_01_sfnt_off0000f570.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF570 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D82 18252 bytes
SHA-256: 5e01cf6db01dcc63f552f73bce74f5be4293e0319c94820209f32d382ecd36ab