Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4ec886023b52aa2…

MALICIOUS

PDF

90.1 KB Created: 2021-10-08 11:32:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: 58a82836def6df40fedc019cd6c2a91c SHA-1: d73f67827a4b667d06267dc9d618893059d04981 SHA-256: c4ec886023b52aa2a97bb12a2586d699700a2bbbffaed3054abd42ecdf65913e
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to a link farm, a common technique for phishing or distributing further malware. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags this behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://newegys.egyseg.eu/ckfinder/userfiles/files/86028653980.pdf In PDF document text
    • http://cableesmaltado.com/d/files/sasejarupilijidavimifu.pdfIn PDF document text
    • https://samirkumarpaul.com/ckfinder/userfiles/files/tukowuwimufosabutofo.pdfIn PDF document text
    • http://sitoad.com/bbqjoekey/files/202109181457124103.pdfIn PDF document text
    • http://studiolorenzoni.eu/userfiles/files/vivoluzisutenidafa.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/c4f8cf0cd5bfe384c573efa1fa97e702/sixewipumoduzabatukoveze.pdfIn PDF document text
    • http://fcraregistration.com/UploadedData/file/12872310356.pdfIn PDF document text
    • http://bephoangdung.vn/uploads/ckfinder/files/bojovekudigu.pdfIn PDF document text
    • http://ucg-eg.com/userfiles/file/62013920140.pdfIn PDF document text
    • http://cukorbetegshop.hu/files/jinijiwonisiduxezexusi.pdfIn PDF document text
    • http://thai-apsproducts.com/file_media/file_image/file/bavirebadesavu.pdfIn PDF document text
    • http://whuntex.ru/userfiles/file/zarolezinuba.pdfIn PDF document text
    • https://xlquality.com/userfiles/file/wivakami.pdfIn PDF document text
    • http://kerrya.com/ckfinder/userfiles/files/kawutowuwobubexaxuwavabog.pdfIn PDF document text
    • http://eko-gospodarstwo.eu/files/file/mozobiludikuletibuv.pdfIn PDF document text
    • https://reparation-mobile.net/userfiles/file/92856988532.pdfIn PDF document text
    • https://optimustelecoms.com/ckfinder/userfiles/files/53049927478.pdfIn PDF document text
    • http://encino.ilovepokebar.com/uploads/files/lofovijerufasodivolezilo.pdfIn PDF document text
    • https://polnische-zaune.de/userfiles/file/lazoravupu.pdfIn PDF document text
    • http://hoya889.com/upfile/files/20210920042844.pdfIn PDF document text
    • http://wenyanchem.com/upload/files/wadefozekigidolilejaz.pdfIn PDF document text
    • http://meyanko.com/userfiles/file///7628073413.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/vazufojavul.pdfIn PDF document text
    • https://smsenerji.com/resimler/files/pokexilevut.pdfIn PDF document text
    • https://esperanzadeavila.com/fotos/file/52327119799.pdfIn PDF document text
    • http://www.biosafety.biz/ckfinder/userfiles/files/gexefexapaselevulubazix.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=how+many+oz+are+in+1+qtPDF 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_off0000f505.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF505 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010d1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D1C 10504 bytes
SHA-256: a84c462f0f9814382a68427ac758eaf06504e3657c203e75f934c9791fc5ac5d
font_02_sfnt_off00012511.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12511 19980 bytes
SHA-256: 1692424f394ebeb4882e1e89dc512e44bc64679d23924d28176dd12b8afef862