Malicious PDF — malware analysis report

Static analysis result for SHA-256 018de55123478f84…

MALICIOUS

PDF

88.6 KB Created: 2021-08-02 01:42:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 805d7adc05a2b81d534fc8b583797205 SHA-1: 7c8e88a0f7606690bf34415425c5986f3e15b875 SHA-256: 018de55123478f8446a31d6996525d54b0b0a6be1ad1b6688ad3904712f63dc3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous URLs pointing to potentially compromised or disposable hosting, suggesting a link farm designed to redirect users. The presence of PDF-specific heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the document is part of a campaign to host malicious content on compromised websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://hengfengpaper.com/filespath/files/20210730015204.pdf
    • http://incomsistema.ru/ckfinder/userfiles/files/vefimu.pdf
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba7816c9d15---38977836154.pdf
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/22ae7ffcd7e775424e06db709414f21e/fomat.pdf
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de4a515bf28---fubogarer.pdf
    • http://ecohost.ru/pics/images/file/3360232488.pdf
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/jhijo3d2imediko1r9ds1thbtv/13293625378.pdf
    • http://sumnerclassof1976.com/clients/4/49/49b54eafcc86ae0c30eb104ab8b91c7c/File/67907873785.pdf
    • http://agataklimowska.pl/userfiles/file/kovozebajukitijo.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607df1e534577---rosujo.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160985d02adfe6---xotuwagobafipanukabuv.pdf
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c623f12be09---81163641381.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098735309af0---namiketuxarakela.pdf
    • http://renovfab-menuiserie.com/userfiles/file/93802744807.pdf
    • https://universitecentrale.net/uploads/FCK_files/file/2019628875.pdf
    • http://52fotki.ru/ckfinder/userfiles/files/visukekapawegili.pdf
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/1aqtbgepmi3500f2i09qgoeq57/luteluluzejerapiw.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609e68a456d66---94874944948.pdf
    • http://xn--o79av69abka850ab6c.com/upload/file/202106270553388295.pdf
    • https://netshopnepal.com/userfiles/file/29709092276.pdf
    • http://www.arborvitae.cz/ckfinder/userfiles/files/pebevuposowudovolifuwe.pdf
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f9d8f926ae---xiworulitoxugatugipekir.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609ca86f7b3f7---nelovemapekim.pdf
    • http://amirafouad.com/uploaded_files/file/foleve.pdf
    • http://aarogyamedico.com/userfiles/file/xipaxafutujeketuba.pdf
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16081e2429e37e---10387998193.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=conjuntos+numericos+exercicios+resolvidos+ensino+fundamental+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f08d.bin
5a8eb43dd8a68813329980d507631c6b6410b66c2da8cc51242c1c47f5cd9ba2
pdf-font-stream PDF embedded font (sfnt) at offset 0xF08D 19216 bytes
font_01_sfnt_off00011fbc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FBC 16792 bytes
font_02_sfnt_off000137d3.bin
b42b40d611ef317707c92409417929aafaee8139077ebd1f7df0253ed74e7faf
pdf-font-stream PDF embedded font (sfnt) at offset 0x137D3 11208 bytes