Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fc7e3872d6c755b…

MALICIOUS

PDF

87.6 KB Created: 2021-06-25 21:07:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: d21bc9933ffa47fe3e479166a64bc73a SHA-1: 75555a877f4779b951c0815a126d6e34db4052fc SHA-256: 3fc7e3872d6c755b2803ec39c3a789218ffbecf2e8ae7b11c1d2042cae92408b
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains a link farm pointing to multiple distinct hosts, many of which are compromised WordPress sites or disposable hosting, suggesting an attempt to distribute malicious content or phish users. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/4ad202070d71a3c6b0f42ab5f02f3645/72533758442.pdf In PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16087e52b7cca8---41498328598.pdfIn PDF document text
    • http://igabana.com/upfolder/e/files/20210606110327.pdfIn PDF document text
    • https://kisikana.hr/userfiles/file/48095450127.pdfIn PDF document text
    • https://businesslife.com/content/file/gikavumotilamusited.pdfIn PDF document text
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/7db63fdcd6c02eae3b14d28c1e42bb12/wogufixitikokuv.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd37bda2ca3---segalawa.pdfIn PDF document text
    • https://thietbidienmanhcuong.com/upload/files/xateminasidiwa.pdfIn PDF document text
    • http://dongfangguohua.com/ckfinder/userfiles/files/vaxilosolofid.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607463c74af91---tiripetog.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1607da52693d17---25865692436.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/an8gsd5gldteetb0f1u158n84i/19540441609.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b2161b1ab08---56444675.pdfIn PDF document text
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/0d6e28949ba8be9e5a6ca844e44ef573/99687352108.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/160916934c6232---11514817129.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/44b15276270f5d40013c6a3a8172a904/38962869834.pdfIn PDF document text
    • https://atraba-holding.com/userfiles/file/timupusilawi.pdfIn PDF document text
    • https://stvorki.ru/files/file/kufakunuwipitodovo.pdfIn PDF document text
    • https://www.kcequipment.com.au/wp-content/plugins/super-forms/uploads/php/files/be03a455676ca058f5a4943ef5f24b9f/wakodewowexufaf.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4f191c5126---fulakopulafemo.pdfIn PDF document text
    • http://inter-travel.hu/_user/file/60087301073.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/vazixugizuje.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16082811ac9036---49130056469.pdfIn PDF document text
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/7abcf74b5417e26f9faf26172cbe7107/koteroxuragosilunoxezofiz.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/e9htam3tl7m7dknfl3ued9i7vf/30806811697.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=what+were+the+first+castles+made+ofPDF 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_off0000f143.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF143 10716 bytes
SHA-256: 9d105548c6be5cc9ebfb72f1ae45e2a0354e5ce55288efa87bde845c8e57c448
font_01_sfnt_off000109f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109F2 18412 bytes
SHA-256: c55ea8a1caba5a8813602abb30c4645014444772972ed38d4e20a9be7b5642e9
font_02_sfnt_off000138ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1