Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a8652ff1587f87c…

MALICIOUS

PDF

82.0 KB Created: 2021-09-22 10:35:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 44346c295e487d37d2724ca3dee30319 SHA-1: 3fbd7919a07eca0db0757f442d28f2035632f63f SHA-256: 1a8652ff1587f87c02853ca726ec72546e5863ea6889f5ee81e2574faeaa15c9
156 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The ML classifier and ClamAV also strongly indicated maliciousness. The document body is heavily obfuscated and likely contains embedded links designed to redirect users to malicious sites, potentially for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://capesociety.ca/uploads/files/7200502251.pdf In PDF document text
    • http://www.koeru.eu/failid/file/47358094619.pdfIn PDF document text
    • http://bibliotekaszamocin.pl/img/upload/files/dajiluxo.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/71632886992.pdfIn PDF document text
    • http://mingmitrcoffee.com/user_img/files/37653629250.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/gowawoluwexijixifin.pdfIn PDF document text
    • https://wyslijpaczki.pl/app/webroot/files/userfiles/file/2140108625.pdfIn PDF document text
    • http://koyomisushi.com/uploads/files/nitipokewomu.pdfIn PDF document text
    • http://cecev.com/stockages/files/88915058310.pdfIn PDF document text
    • http://jowinbio.com/upload/files/202109181143347754.pdfIn PDF document text
    • http://bkdesign.ee/userfiles/file/vawekutomejanokenaj.pdfIn PDF document text
    • http://alsace.annuaire-regional.com/ckfinder/userfiles/files/monujenarimubimapiteluti.pdfIn PDF document text
    • http://hycxchina.com/filespath/files/20210920031822.pdfIn PDF document text
    • https://grandegroup.net/files/59028948640.pdfIn PDF document text
    • http://burchiellati.com/file_fck/file/sajilizeso.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/16148f484e8f79---69948780843.pdfIn PDF document text
    • https://war-old.its.vn/new/userfiles/file/sixibigazev.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/8b70c2369ad06ce3524dc50b602f7c4f/95758267937.pdfIn PDF document text
    • https://8cj2aja7-8mxb.com/contents/files/44190978727.pdfIn PDF document text
    • https://www.greenlakecruises.com/ckfinder/userfiles/files/10349314525.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16145323748e61---63015739197.pdfIn PDF document text
    • http://duythuc-bearing.vn/uploads/userfiles/file/51904933167.pdfIn PDF document text
    • http://pereplanirovkaoblast.ru/pict/file/miwomasuko.pdfIn PDF document text
    • http://olymp-kiev.com/temp/fckeditor/file/babixefuvere.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=samsung+galaxy+s4+touch+screen+calibrationPDF link annotation
    • https://forums.androidcentral.com/showthread.php?t=369745&s=75a2aba2dcd71e70650e385604771cb1&p=35035In 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
    • https://forums.androidcentral.com/showthread.php?t=369745&s=75a2aba2dcd71e70650e385604771cb1&p=35035In 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_off0000dae5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE5 11284 bytes
SHA-256: 6f64e082f60757c0559b5d489a80636769446d20486dc34b58001300e6c862a0
font_01_sfnt_off0000f546.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF546 17560 bytes
SHA-256: 55317c98b920d03cbe189319002c71d261957342281966fee78a82930ff1738b
font_02_sfnt_off000122a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1