Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f8136f565d6b028…

MALICIOUS

PDF

83.4 KB Created: 2021-09-16 01:04:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7acfb6e5b08336e51aee215286ff9909 SHA-1: 6ded9e800c90774b3acd3a992679276f9ce3bd7e SHA-256: 6f8136f565d6b028871c45bb684c9fb0e54b7abce00105bb195b939783efc814
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or are hosted on disposable domains, suggesting an attempt to lure users to malicious content. The PDF structure itself appears to be a link farm, a common tactic for phishing and malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://gadkowski.pl/repository/filemanager/file/82413954993.pdf In PDF document text
    • https://tasivn.com/upload/ck/files/bupedikujawu.pdfIn PDF document text
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/bozisopigatomosuzed.pdfIn PDF document text
    • http://sterenstein.ru/userfiles/file/dadaw.pdfIn PDF document text
    • https://www.ccs-corporation.com/ckfinder/userfiles/files/tugisogusuxu.pdfIn PDF document text
    • http://shortguycentral.com/ck_uploads/files/ramuralujupak.pdfIn PDF document text
    • http://gesht.ru/admin/ckfinder/userfiles/files/larozozilejosetotavu.pdfIn PDF document text
    • https://asiquim.com/ckfinder/userfiles/files/tepodaluzo.pdfIn PDF document text
    • https://cremyco.com/app/webroot/docs/file/vumix.pdfIn PDF document text
    • https://glycocalyx.nl/userfiles/image/file/diwizi.pdfIn PDF document text
    • https://www.hsbofmn.com/ckfinder/userfiles/files/jokifomeretuka.pdfIn PDF document text
    • http://ikkosushi.com/uploads/files/92098818956.pdfIn PDF document text
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/35773636451.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/6f84641acfa672c6f7c3746c552ed6ac/gawokuradogivobuboboxesu.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613e404ab8c16---senajexegedeg.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/fuxazevepuvoxozegekus.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613965885d5eb---64441441692.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/rabawijotazoxigobekosako.pdfIn PDF document text
    • http://gallery4walls.com/upload/editer/file/75190146821.pdfIn PDF document text
    • http://norilsk.torbay.ru/images/uploads/file/ditezino.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=fast+furious+9+1080pPDF 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_off0000d942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD942 10696 bytes
SHA-256: efb855131e23ab16608f493c45e368d7e22f71e8011e9df20adcd46af5e3c3ad
font_01_sfnt_off0000f1fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FC 20068 bytes
SHA-256: 2337b297f1986a6f0a1e4ab0009625d15ac3470771c980fd7c61671ad2ee19d5
font_02_sfnt_off00012697.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12697 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1