Malicious PDF — malware analysis report

Static analysis result for SHA-256 43525074f3cc235f…

MALICIOUS

PDF

86.9 KB Created: 2021-09-05 14:04:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9020dae6ee769394f196e98738091b19 SHA-1: 497edbdcb74fa7a419bb9a0f1db277fb75e03a14 SHA-256: 43525074f3cc235fbeb2f22af6f8fbcd3a295249a4be6317949b67b8f77a6884
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the heuristic findings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/16102eefb9adc1---4979274146.pdf In PDF document text
    • https://noblacklist.pro/web/img/podborky/files/luxad.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0cc85dc0e---xutozefowezavupozelegevuj.pdfIn PDF document text
    • http://toyteepee.com/uploadfiles/file/210521214257992266ckkmj8.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/40167470923.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/16102fb58afe03---xufapinudusuv.pdfIn PDF document text
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/7d87b56aa275d5d076664171a13338b5/mivepusotuzigoxexavigeze.pdfIn PDF document text
    • http://www.bufolari.com/public/immagini/file/sizowubewelan.pdfIn PDF document text
    • http://slsnn.ru/content/file/51393122596.pdfIn PDF document text
    • http://schubert-hh.de/image/file/fugesugumejafe.pdfIn PDF document text
    • http://scea.edu.mn/ckfinder/userfiles/files/gasukomereweboroxafeli.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085b14cd5c9a---tireku.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/zedubemirovejajumumoku.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c03302b2302---kopesa.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084ddd3ec2b2---49201041252.pdfIn PDF document text
    • http://moristas.com/userfiles/files/kotadepapijixozuji.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/5pjj4l3318qd9o2f46hopq2mg1/duzatugeketurozowumarob.pdfIn PDF document text
    • https://thehero88vip.com/ckfinder/images_store/files/94976708488.pdfIn PDF document text
    • https://www.kasekimi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cabed662eb---70327884749.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af6801ef89a---26534706185.pdfIn PDF document text
    • https://lanegarrett.net/userfiles/file/zoweritumozirerar.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/fomuxavasowekapip.pdfIn PDF document text
    • https://questyme.com/userfiles/file/gudejulov.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160736b3fa0ca5---40619487336.pdfIn PDF document text
    • https://chezgregoire.fr/userfiles/48972192537.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=necromancy+spells+pdfPDF 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_off0000e78a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE78A 10684 bytes
SHA-256: f6e37ab33da3a9b9317b00c665401259af5bcc330c9a850459a1022bb99a36e2
font_01_sfnt_off0001000e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1000E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011820.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11820 20392 bytes
SHA-256: 04e4e5cfcf9d5c9de33bffaf73bd40399bf3a1484126513ea8f8b6252cecadf7