Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b71c97ec3759ba0…

MALICIOUS

PDF

98.5 KB Created: 2021-07-13 18:20:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 527b1a2c5713889b33982aac611e0553 SHA-1: 5fda9b08c802de32d81a6188413c577b43ddaca3 SHA-256: 7b71c97ec3759ba0b82b6442bd56e278956f76fde45b478550fc26f6058ca000
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of multiple compromised CMS upload links reinforces the phishing pretext.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6210e7f1d---jananivonibi.pdf In PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160c00963994cd---45544022420.pdfIn PDF document text
    • http://grandp.ru/userfiles/file/mipewadugexawemesak.pdfIn PDF document text
    • http://schokoladenfontaene.de/idata/70690793859.pdfIn PDF document text
    • https://ceccarbotosani.ro/userfiles/file/56956275089.pdfIn PDF document text
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/agl4oaak2fav4hhtkbr98la645/82383469425.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/kavafer.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160da45ecd105d---xibisadubibuvubetuveko.pdfIn PDF document text
    • http://prime-standard.com/piceditor/file/mutigizugatujezumoxis.pdfIn PDF document text
    • http://sugarfree-gelato.com/upload/file/70607978341.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/3e7357fa2bd040fae670945274d98ab6/defuj.pdfIn PDF document text
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/f4b04e473f9c50991fc7970a7cb4692f/jotogeda.pdfIn PDF document text
    • https://www.rekalibracija.com/wp-content/plugins/super-forms/uploads/php/files/e9d020cffaddad43f9f1dc3f028b9a5b/32173799946.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/wavifefuvoboxitalazuma.pdfIn PDF document text
    • http://bidmitt.com/img/files/file/mefanedupe.pdfIn PDF document text
    • https://teenvolunteerhouston.com/wp-content/plugins/super-forms/uploads/php/files/cebeb27ab13b93f609a7164278527e15/52653722031.pdfIn PDF document text
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a83ba9e6547---farixoga.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/dggssh68jl43of6pb5joq24f16/15554846629.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a62256f1b---nusosakuwup.pdfIn PDF document text
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/f595242a3b4709344d978789d86a9dbb/rozefakekovipomolite.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/cb85daf410272f7a5fd923286e8bccdd/kivuzuwap.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160b2867d71011---niderikegixoxabus.pdfIn PDF document text
    • http://futurepoolandspa.com/ckfinder/userfiles/files/33159937699.pdfIn PDF document text
    • http://thomasbelldescendants.com/clients/40432/File/mofifosatogizobu.pdfIn PDF document text
    • http://hillcresthigh1971.com/clients/9/9f/9fbf9047a6869172a982db6f42f05a9a/File/21462333504.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=playing+d+and+dPDF 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_off00012035.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12035 17660 bytes
SHA-256: ed31fa701a3172cb5812d7a16e6dd544f0937bcac21213b3322357f5535f8997
font_01_sfnt_off00014eec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016702.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16702 9920 bytes
SHA-256: e8ea4e1f088007b771b99074f0a696ac8ee1349b49988a6819a64a11f9a787d1