Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6fac9777910cc1e…

MALICIOUS

PDF

82.7 KB Created: 2021-09-08 16:47:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: aa8d77cee229b9b1761d14eb62be3930 SHA-1: 9e2f42cf01e1b505bd1cb573a79fca8d6a60e299 SHA-256: c6fac9777910cc1efdc983d5d8f0acce19d6ceee393039886d0d685f28c819eb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of link farms hosted on potentially compromised or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://crysiq.ru/uplcv?utm_term=autocad+tutorial+2016+pdf PDF link annotation
    • https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/vedixupodo.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/33592552147.pdfIn PDF document text
    • http://lovepetclinics.com/file_media/file_image/file/zapokowufebup.pdfIn PDF document text
    • http://razzledazzleevents.in/userfiles/file/40177010713.pdfIn PDF document text
    • http://kite-surf.sk/files/jigivikupamutafedanim.pdfIn PDF document text
    • http://neonatal-surgery.ru/userfiles/files/1840017218.pdfIn PDF document text
    • https://5udua.com/contents/files/6948724674.pdfIn PDF document text
    • http://hhsmelt.com/upload/files/getez.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16132aabca70b7---borulejopekowipejexeti.pdfIn PDF document text
    • https://nezrenweb.com/calisma2/files/uploads/bezevetupibukada.pdfIn PDF document text
    • http://refah4ter.info/basefile/hotelrefah4terir/files/jogujenakolivafujabuzufu.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc759e6d74---lefozasisuruboduresez.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613462b02aa04---38134911838.pdfIn PDF document text
    • https://pfhotel.gr/ckfinder/userfiles/files/vutarefijiguxesa.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/470f455f310039097686fbf3bcb7cf46/lafagalulotorudupo.pdfIn PDF document text
    • http://conhantaoankhanh.com/webroot/img/files/xovamiwipuge.pdfIn PDF document text
    • https://zohopin.com/calisma2/files/uploads/folenoj.pdfIn PDF document text
    • http://dissanna.com/temp/fckeditor/file/terepala.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/161377484b70e1---wopesuj.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/92448463820.pdfIn PDF document text
    • https://thietbigas.net/media/files/mabavemefawo.pdfIn PDF document text
    • https://birotex.rs/images/files/62172194764.pdfIn PDF document text
    • http://cerritos.songhakbbq.com/uploads/files/87061166942.pdfIn PDF document text
    • 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_off0000de0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE0B 10752 bytes
SHA-256: 43cf81d678f65d7431cc424eab58be474cd3b06966d7e989b866f4c2fd12e5f7
font_01_sfnt_off0000f6f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6F4 17776 bytes
SHA-256: 4f81e245c89e73caca5e98840488ffcc96463f6142a4a21d82641d22fecd377f
font_02_sfnt_off0001251a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1251A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1