Malicious PDF — malware analysis report

Static analysis result for SHA-256 881bb97491b12925…

MALICIOUS

PDF

90.7 KB Created: 2021-06-29 07:16:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 52224f72f14d87daefb7d5e243921e6e SHA-1: 94c7a74219afaabfec4ffa75151bb379844a8600 SHA-256: 881bb97491b129254254a05f3899ede56d24acfa4f0b2fac26835a30c029eb25
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document contains numerous embedded links, many pointing to compromised WordPress upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the heuristic firings and URL analysis are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://baxsporthorses.nl/userfiles/file/67195591149.pdf In PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/khhn77fcdcq2upa3837fs3hs8b/5286387839.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/807c6f2aa512fe6b4bd19b21b1b3d931/zekijisoxatotipimirawim.pdfIn PDF document text
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/qhu4qestp9ha44dl6mou7h3j90/pifejakukedabamu.pdfIn PDF document text
    • http://lapenya.cat/imgjovesnaves/file/9522521729.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/8bvl4lqkbp4uq0jdkd182948vr/tepipukakasinus.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/31303948968.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/t5a2g0afmfo31i8fus32vjmnat/16807958076.pdfIn PDF document text
    • https://plentis.eu/ckfinder/userfiles/files/83563722376.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/3osea7juhckih4dtrl4sqmse6o/pofosidobuv.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/36f4c019525bef1b9c0e1f5adefda17f/ravomamitinifekuxojopunej.pdfIn PDF document text
    • http://all-pass.com/folder/editor/file/41715245767.pdfIn PDF document text
    • http://brownewingfamily.com/clients/a/a4/a4d7a48ed280e719b438ae57db99af5e/File/kuwenerutumut.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c1b5ebf05ec---terodolorosisovetanu.pdfIn PDF document text
    • http://chiengthai.com/file_media/file_image/file/39529649927.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/oqfumtp6hi2ln595q0d091clf8/xofexuw.pdfIn PDF document text
    • http://safetypath.net/cms_images/jiruzopoxegobazek.pdfIn PDF document text
    • http://www.toeterloeh44.de/files/42101311083.pdfIn PDF document text
    • http://canadapremiumlubes.com/survey/userfiles/files/69406656692.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/450d12e642e16f623cc3458faced7415/nanijumepubukumepixopefu.pdfIn PDF document text
    • http://brainbond.ro/userfiles/file/67170052480.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b94a0b279b1---kujasawuveder.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c53c168b89---xepekoziki.pdfIn PDF document text
    • http://www.euro-fly.eu/userfiles/files/fikarerimezupiko.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160d44d6ede447---kitikatu.pdfIn PDF document text
    • https://www.fliIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=different+types+of+funnel+web+spidersPDF link annotation
    • 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_off0000ff71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF71 10772 bytes
SHA-256: 64ed4d93562ecc9bf7bd50d21072699af613109f70ccd0f5d26788116c2bc86e
font_01_sfnt_off00011830.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11830 17120 bytes
SHA-256: 42dcd506818c30a0a485c0a3cf87e1dd60ed21a64882db9d54e3b7c3ccca696e
font_02_sfnt_off0001450f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1450F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1