Malicious PDF — malware analysis report

Static analysis result for SHA-256 da83c37e45f55906…

MALICIOUS

PDF

84.0 KB Created: 2021-07-07 00:11:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b3c710a7db17a4ae81637238e582d3e0 SHA-1: d26827a155ee3f9bcbcc13dcad6a21494e2cc207 SHA-256: da83c37e45f5590629f8ecdc0dddb4b8ff227ec01dc7a1658e25877b5b55a965
156 Risk Score

Malware Insights

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

The PDF contains a large number of external URIs, many of which point to compromised WordPress sites hosting other PDF files. This behavior is indicative of a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a17a95b39dd---tasisizofozaxujasi.pdf In PDF document text
    • http://mosvag.ru/img/lib/file/nidenonefu.pdfIn PDF document text
    • http://dlikefulproductions.com/clients/875850/File/rijefaneveg.pdfIn PDF document text
    • https://www.shropshirefurniture.co.uk/admin/ckfinder/userfiles/files/12785148794.pdfIn PDF document text
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c8996243e2---75413326986.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606fc2112b782---5114628054.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c140bea5cfc---pumuj.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1607be7a497c8d---55695374996.pdfIn PDF document text
    • https://cncostruzioni.com/userfiles/file/18984152208.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/gepatukat.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160730fc208661---83484844416.pdfIn PDF document text
    • http://thaimassageboy.com/ckfinder/userfiles/files/lifenagusimutabegifitave.pdfIn PDF document text
    • http://cosmosimpex.com/app/webroot/ckfinder/userfiles/files/74250539144.pdfIn PDF document text
    • http://maychamsocda.vn/images/userfiles/file/zenatavikalexuwofo.pdfIn PDF document text
    • https://artenika.pl/fck/file/59021953888.pdfIn PDF document text
    • http://magyaringatlanadatbazis.hu/dev/_user/file/64242350985.pdfIn PDF document text
    • http://dralituncer.net/userfiles/file/goworibin.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160abe41a1186f---xanutataxavabojapovetaxog.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/4l5ql7kpj1k304fg8gtpfs1s7u/revojasopewusufig.pdfIn PDF document text
    • http://www.melloecastro.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dbb48c2093---16032121377.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16087202141922---fofupaxipoj.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/b36acc72fd0bc44406be5bbf9876f4fa/tiwiripusaxisawaxexab.pdfIn PDF document text
    • http://donahoelawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/249081471.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=modern+blood+banking+and+transfusion+practices+7th+edition+pdf+freePDF 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_off0000e24b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE24B 11276 bytes
SHA-256: 1319dbd98c31aa85207b9df93bf973a58ec4817dd59272b33a9d068b88ab3e66
font_01_sfnt_off0000fc56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC56 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011468.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11468 17392 bytes
SHA-256: fd8fece6d0433866d0bbeb8ceabb572a6a423a478528da8a8d1fc5f494b47eb8