Malicious PDF — malware analysis report

Static analysis result for SHA-256 81ab312cd2ff1c25…

MALICIOUS

PDF

78.6 KB Created: 2021-07-14 04:43:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 88238c96c996fc78df7ee045f4260a43 SHA-1: 87be1f026766af8c27fdfe159777791f2eb9018d SHA-256: 81ab312cd2ff1c25f18c07086e845480f84f65ca2d85824db878c4b61b5ab5a7
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting it's designed to lead users to malicious content or phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160e4311d15e66---60060072432.pdf In PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5d7097666---majopowepofolalazazuduro.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/t0h7lkqf963iifb29i0icdm6mi/mesafodivaxovuge.pdfIn PDF document text
    • http://daearesort.com/FileData/ckfinder/files/20210604_3A4EF42D9FF573EC.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160ba013c0d705---ledugodenagagopitiduj.pdfIn PDF document text
    • https://nepalipublisher.com/ckfinder/userfiles/files/repabuxepogoxunomosinex.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c470c69b30---87485211997.pdfIn PDF document text
    • http://thallo-food.hu/uploads/ckfinder/userfiles/files/zamuku.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/mlrrldsck6vkplct73cpi4ri13/32086659324.pdfIn PDF document text
    • http://progfin.pl/userfiles/file/wozipiluxurapubipamutu.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/27ea6787c9b2a72607da5a18707115a8/76298128883.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8454262d1---52050720406.pdfIn PDF document text
    • https://media-get.ru/userfiles/files/57360280161.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fb3fa330fc---31731449244.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609630f0b3dd7---zepajemeginigunotizemu.pdfIn PDF document text
    • https://barcelonamedicalcenter.com/files/galeria/files/netixaxowerizanubavefufez.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160bc22bae9dc5---rofowopilijevewejewerisu.pdfIn PDF document text
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160829f753ecc7---39405638805.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/l1fak5j2di6802pukua79vaiqe/regupofazus.pdfIn PDF document text
    • http://stpatricksreunion.com/clients/84553/File/65874768984.pdfIn PDF document text
    • http://maynenkhipuma.vn/quangbasanpham/app/webroot/upload/image/files/direzamukijasu.pdfIn PDF document text
    • http://syarmarka.ru/userfiles/files/lemojunugelumitid.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609be292233f1---18903248154.pdfIn PDF document text
    • http://kuppersbusch-center.ru/uploads/files/wokotupinojamivipu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=06+ford+f150+owners+manualPDF 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_off0000cd88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD88 17372 bytes
SHA-256: 6b905927a6d779eb8bed56e8eb77cf2c8fb112066673dc6e49eeae3953e4dec6
font_01_sfnt_off0000f9ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9ED 10892 bytes
SHA-256: 83d6c32a500c5ea57a8692859238b83df871eb1dd3ffca8bebcb63e84d1b2b43
font_02_sfnt_off00011346.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11346 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1