Malicious PDF — malware analysis report

Static analysis result for SHA-256 491b6ea9d2d75115…

MALICIOUS

PDF

89.7 KB Created: 2021-06-27 21:58:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6f46e1a53675297366cb98a6154228f7 SHA-1: 503f84ac8ec0ddcd0e19256d5dc386d727f7566b SHA-256: 491b6ea9d2d7511550e466a06647dd1316d6cb28c0aec085f34aeff879f82f23
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The file contains a large number of embedded URLs, many pointing to compromised WordPress sites, suggesting it is part of a link farm used for phishing or spam distribution. No scripts were extracted from this sample, but the extensive use of external links indicates a likely attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://pistant.ru/uplcv?utm_term=all+possible+dittos+in+pokemon+go
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/609bee18a278629bb3f23f0061db5c82/zuwejugapibejone.pdf
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160ac52ee6c8f5---51190836238.pdf
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/94fbae1d88bd8967270c58c0f9e4ebce/tuwuruxofevakowegijari.pdf
    • http://randoquad72.fr/userfiles/file/lugubexu.pdf
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/904103705bd169bb28d8732497495542/novalefejewitaza.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6ae4493aed---60793897458.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a4299bef656---bujanugeses.pdf
    • http://harposwebdesign.nl/app/webroot/files/userfiles/files/bexuvek.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/160895c7d45b01---gowugedewamoxepisiropatat.pdf
    • https://gertiesbloomers.com/kousumi/nulook/upload/fckimages/file/47808085633.pdf
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a4cbf4db5c3---nakefibukedof.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/1cd1eae71eaaa1c8a2c6db95d7784436/mekiruwaned.pdf
    • https://universal4shipping.net/userfiles/file/83322126466.pdf
    • http://train-in-japan.com/images/blog//file/wobir.pdf
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607c49ddbb3d4---fofanavetinaduxokomuxow.pdf
    • http://coclub-us.com/ckupload/files/21316548177.pdf
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086ee7cc39c3---18830266066.pdf
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac031f2fd9---66826592963.pdf
    • http://ithaca1960.com/clients/8/87/874e400c25abfb160fd1c0cf9913fcd0/File/47862647079.pdf
    • https://rkdestate.com/userfiles/file/vikazavokiwoxat.pdf
    • https://hse.tw/upload/file/labibegiwujigoperuxim.pdf
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bffa5590bdc---wuvokutoxijur.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/c1917d6a22bdac432f7a8420c80b5810/65823049045.pdf
    • http://psychologyforeverybody.com/ckfinder/userfiles/files/baxax.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_off0000fa81.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA81 16792 bytes
font_01_sfnt_off00011298.bin
2227df2f35eadcb89292407a1701ae7b1cf8b1a36be8819e56ac453082eb9e71
pdf-font-stream PDF embedded font (sfnt) at offset 0x11298 10688 bytes
font_02_sfnt_off00012aa8.bin
946748feb57afba5810914a2f7c9377951dea5190ba9a30b9b4551b0b31017e5
pdf-font-stream PDF embedded font (sfnt) at offset 0x12AA8 17356 bytes