Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cb22b930e81aa66…

MALICIOUS

PDF

81.9 KB Created: 2021-09-21 06:50:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ba7281fb7f35a8c856b5d15fa26e69d3 SHA-1: d0266b6ae4434ffc81440686cd0fd176d51d5c4a SHA-256: 8cb22b930e81aa66d12dc8669b25bf3f036e2a80049e03b260b312e8f2523033
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm or phishing lure. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to facilitate the malicious links.

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://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d36e66d0f5---59830146826.pdf In PDF document text
    • https://forumhrdbekasi.com/webroot/userfiles/files/30716417714.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/161327863ee948---28776429231.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130b557b2f58---pofijunurulenakitovapisan.pdfIn PDF document text
    • https://pierreseche.fr/userfiles/file/nafakipizebavaxa.pdfIn PDF document text
    • https://spyboarcams.com/files/supogedofajuwasokubuxeru.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/2k4ev04o9emqbp2gqhstkmugaa/3232498774.pdfIn PDF document text
    • http://aminotp.com/upload/files/82150139365.pdfIn PDF document text
    • https://oilbasaro.com/web/images/ckfinder/files/20210910062032.pdfIn PDF document text
    • http://nfraccon.org/userfiles/file/56263442934.pdfIn PDF document text
    • http://sergeybazarov.ru/file/65693648617.pdfIn PDF document text
    • http://ltpbetel.ro/userfiles/file/kewasafebexifi.pdfIn PDF document text
    • https://saint-florentin.charcutier-traiteur.fr/ckfinder/userfiles/files/78743574449.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/7308b85e5121cf671b3f32d636d869fa/pomobivuzuzas.pdfIn PDF document text
    • https://bwhe.in/ckfinder/userfiles/files/davumelubawerimonipafalu.pdfIn PDF document text
    • http://reckdance.pl/userfiles/file/koxelokunu.pdfIn PDF document text
    • http://selidbe-beograd.info/files/gemifatafetuxufejusefin.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/0eaadd8f5969ee59c1b85d61f2144e31/faditijutuwi.pdfIn PDF document text
    • http://asja-doll.ru/userfiles/file/46377666121.pdfIn PDF document text
    • http://elverum-revmatiker.no/images/file/tufazapesaxakelivetur.pdfIn PDF document text
    • http://munnartourism.com/uploads/file/29429149325.pdfIn PDF document text
    • http://abbeytraining.net/userfiles/file/88239566636.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16132eb8247e31---14461630931.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/gctp98av0ov11ir89ecd5ja1sj/28053216879.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=extreme+car+driving+simulator+2+hackPDF 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_off0000dacf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDACF 17548 bytes
SHA-256: 50e2d285cef14d93d38720ef69ec8e32b1b1c78871dcd7fbdb5e6f81eeab36e1
font_01_sfnt_off00010801.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10801 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012018.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12018 11280 bytes
SHA-256: 4e284ff4c6dae9c23e7b3cf6bc7a69d803813113106bab48de9b361cfbf67dc9