Malicious PDF — malware analysis report

Static analysis result for SHA-256 31fde0c0ef988aba…

MALICIOUS

PDF

90.5 KB Created: 2021-07-06 20:12:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ebbe0da2f2d0d26b131dc851261d30f9 SHA-1: 7e9ef58dcb29c2e83aaf10bd6e8e599864f7adc1 SHA-256: 31fde0c0ef988abab9243994b09182a71940d9ef0fec5192f6f62a1e9edfee44
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a large number of external links, many of which point to compromised WordPress upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. No scripts were extracted, but the link farm structure itself is the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://zemiigori.com/uploads/file/74989386725.pdf In PDF document text
    • http://esoftland.com/userfiles/file/418735995.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/869811e291aa1a376d8004691900a7ce/wipakiwasosigu.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af4a341a231---29235077218.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a0296f31b84---kefurabejujutege.pdfIn PDF document text
    • http://unipsyclinic.com/userfiles/file/20210508130903.pdfIn PDF document text
    • http://musikpark-live.de/userfiles/file/jitodudexagirekik.pdfIn PDF document text
    • https://chp-travel.ir/data/file/20484823641.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c243524a1f6---74094318902.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/559bd5c125027f187ecbb9437e0fdd6b/45257103234.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/16094add7a37ed---49770789159.pdfIn PDF document text
    • http://stasta.com/userfiles/file/34990240571.pdfIn PDF document text
    • http://wittlich-luexem.de/userfiles/file/wuloxikexafoko.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/16070530e3d559---10576318265.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160bd4c1accd38---tumotuvaselameza.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/7e927092db0c3a86af1be8da83043646/20093762991.pdfIn PDF document text
    • http://cathyknightwaite.com/ckfinder/userfiles/files/dogomogibarutoburubuwa.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce98af01df---38486597252.pdfIn PDF document text
    • http://anatolianlgs.com/userfiles/file/jigusuderujepimaledo.pdfIn PDF document text
    • http://skoleniridicubrno.cz/ckfinder/userfiles/files/ruxobogo.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/0675fae3fad879dbd01b9ac250e5ea2e/mijinexozukidaxova.pdfIn PDF document text
    • http://montrealinkwell.com/clients/c/c4/c478fb9048b4d856ed1aa16e2301f982/File/19236236748.pdfIn PDF document text
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/eb340f3be5414c774d090fd51e377ba5/78659217602.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/cfb1644a049dc31baba15d6279fceb16/75468620477.pdfIn PDF document text
    • http://hpworld.hu/data/pic/Image/file/vabavajuzawusitexiwud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=cabbage+gas+reliefPDF 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_off00010158.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10158 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001196f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1196F 10240 bytes
SHA-256: 195ea186bb8b20ad054587e4a812a91d8f3acc03e16c1c3c4dd6e6b2ef331f12
font_02_sfnt_off0001308b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1308B 17132 bytes
SHA-256: a738c025e84424318819b6f4194a6ec3e3cdce64250f0f7c6989570b6fea2c0d