Malicious PDF — malware analysis report

Static analysis result for SHA-256 ee499d3ac25077b1…

MALICIOUS

PDF

76.8 KB Created: 2021-09-17 06:33:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: f8daa865192c5f7f0bf4388ffbb83f08 SHA-1: a7ce81d792b6cbf81f070913bfc3408eb860f8ed SHA-256: ee499d3ac25077b1d9de7997ab07cd9bffb78a0bb6862f1d2c7b9ce4227a2dd6
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to other PDF files hosted on various domains, indicating a link farm. Several heuristics suggest these links are part of a SEO manipulation scheme or potentially a phishing lure, directing users to content on compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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://www.asoriofrio.org/ckfinder/userfiles/files/vugulokiwo.pdf In PDF document text
    • http://pitchdecor-construction.com/user_img/files/vumumekenonimuxu.pdfIn PDF document text
    • http://zensushialiso.com/uploads/files/soxozut.pdfIn PDF document text
    • http://www.groupementpecheduloir.com/ckfinder/userfiles/files/26422985394.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/68463121343.pdfIn PDF document text
    • https://goodmix-psc.com/userfiles/files/52745959436.pdfIn PDF document text
    • http://lamachine.nl/userfiles/file/19616050567.pdfIn PDF document text
    • http://asijskepotraviny.cz/files/file/10775534823.pdfIn PDF document text
    • http://gloteckr.com/upload/editor/file/67965080373.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161322e890317b---69656886741.pdfIn PDF document text
    • http://obkladlazby.cz/userfiles/file/83748305892.pdfIn PDF document text
    • https://j26clean.com/upload/files/winuwodowevesasu.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/3259f7940820cea369bc7468eef10f44/41960937386.pdfIn PDF document text
    • https://foodvellythailand.com/upload/files/93831520294.pdfIn PDF document text
    • http://helloslow.com/data/userfiles/files/vasemakilewonag.pdfIn PDF document text
    • http://nelly-design.ru/upload/files/xowav.pdfIn PDF document text
    • http://lonerangerfanclub.com/ckfinder/userfiles/files/pulomusu.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/13bd262d3331b12a519e3dc0afaf2eea/jajovabebuzesojuvobi.pdfIn PDF document text
    • http://flex-link.cn/uploadfiles/files/58685481582.pdfIn PDF document text
    • https://christianklein.eu/Quansis/ckfinder/userfiles/files/zozeb.pdfIn PDF document text
    • http://xszhuhai.com/uploadfiles/files/netotuvepinumetowupe.pdfIn PDF document text
    • http://isotech.si/uporabnik/file/20084329796.pdfIn PDF document text
    • https://nutritie-metabolism-sanatate.ro/app/webroot/files/userfiles/files/74499726058.pdfIn PDF document text
    • http://www.enjoyvaltellina.it/admin/ckfinder/userfiles/files/12667790864.pdfIn PDF document text
    • https://mercerapparelss.com/userfiles/files/nemad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=download+grand+theft+san+andreas+for+ppssppPDF 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_off0000c63f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC63F 10772 bytes
SHA-256: 3e5ecb89f25b05add55f1fbfd91cdd1a6b1586479c00123839381ed590bfa435
font_01_sfnt_off0000ded8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDED8 17980 bytes
SHA-256: c6ab452f6c841978554762ac2ddd29add0e1ce0745d0e0f7c14cceb7054015cb
font_02_sfnt_off00010d89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D89 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1