Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5f1f7b055354f91…

MALICIOUS

PDF

83.0 KB Created: 2021-08-15 14:33:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c5797a2b126dd1ab2fbaeac777dbe7b4 SHA-1: 2a068d7a5be0e0c180a7e97137b99d39ea30d66c SHA-256: a5f1f7b055354f91471ef8782e5bb03a514af606b985f0e7b2128f20021f06b5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. Heuristics identified it as a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to redirect users to malicious content. The document body was unreadable, but the presence of numerous unknown URLs strongly supports the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

Heuristics 6

  • 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.
  • 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://allseasonsbanquet.com/clients/868236/File/nojenikodenekamaw.pdf In PDF document text
    • http://ore-processing.ru/d/files/borovugezokes.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a39dfbabd5f---20020132689.pdfIn PDF document text
    • http://cu-hinothai.com/ckfinder/userfiles/files/43387519444.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/80810571797.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/3ptm0tqdl0quenj12o18spm4b0/61713853609.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/nj2kbi01l910vt5ful6uqqg357/21719049661.pdfIn PDF document text
    • https://digitaldaya.com/imagenes/file/pubilasotatovogapokom.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e71b1c2692---98399148609.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071fd1d3a0c0---38133053759.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea2551f7a1---29937511135.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/1ekmqlnna5mk0iodtj5ls4165a/71243878273.pdfIn PDF document text
    • https://bushregenerators.com/userfiles/files/bonemole.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/ziminanet.pdfIn PDF document text
    • http://centralcogtc.com/uploads/file/feziladawuwixotarak.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e1d43229a---vajujuvebarovovenebadog.pdfIn PDF document text
    • http://casier-a-bouteilles.fr/file/20427705293.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/rf6ulnc870lac7d64v6mc56kf1/60309077380.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/wadotijojonoropododuloluf.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/e6ac6ae467c8aa8503d92069b2afdcfc/foteburorozifiliwadeb.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075792da2c34---15183934841.pdfIn PDF document text
    • http://frappsreagent.com/upload/files/18798558510.pdfIn PDF document text
    • http://acevina.com/webroot/img/files/xepidawakeridapixuwexuj.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160852d58cc321---30025583201.pdfIn PDF document text
    • http://short-story.ru/upload/file/suwokelu.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16098c7fae31e0---26087652580.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=twilight+6+release+date+australiaPDF 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_off0000dfbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFBF 17452 bytes
SHA-256: 7e3467e791ef13190458ad24deb5581f584b5071f17c4e3a3c7192c67c1d8c85
font_01_sfnt_off00010d54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D54 10620 bytes
SHA-256: 90e09f9f2a55ef484e03daed54b0fc3218782e4ae8b8309c661cf481a25168a5
font_02_sfnt_off000125a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125A5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1