Malicious PDF — malware analysis report

Static analysis result for SHA-256 540a882f20025f02…

MALICIOUS

PDF

86.3 KB Created: 2021-07-31 23:10:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5f49c3ff3705e13036b170a7f3753290 SHA-1: 338ff6562c98ed123d0f02f523fed304a01fe2ac SHA-256: 540a882f20025f02ee7fb6e330395e0d6cf3fb03e48f68f58b05647a70e26203
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the presence of a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute malicious links. The document body is unreadable binary data, providing no direct user-facing lure.

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 http://mpu-beratung-brendle.de/userfiles/file/42246599734.pdf In PDF document text
    • http://maychamsocda.vn/images/userfiles/file/18128053895.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/cbf73ca75bb2e3b3a0d903dfd1d3cde6/24831527366.pdfIn PDF document text
    • https://synersys.fr/contenu/file/76033720152.pdfIn PDF document text
    • http://candientuvibra.com/images/file/65562077270.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c9cc4702f1015e5355a78caf6a11398b/diwugowudot.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/8b61fdc4a35e2941770f0f2245dcd6af/72644034841.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd574076cf---temadusasawa.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16084e2ec59bea---95960354981.pdfIn PDF document text
    • https://nhathuydesign.com/wp-content/plugins/super-forms/uploads/php/files/l8aeq13igt5dbsefoe8nqdo7kr/vabewiwut.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095e73543309---vagesedileninu.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/16076b35d89089---22759077715.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079eae279e43---76590278390.pdfIn PDF document text
    • http://mp-journal.com/media/file/gukexevodipusazabu.pdfIn PDF document text
    • https://people11people.gr/uploads/File/89866178987.pdfIn PDF document text
    • http://thcsducthang.pgdbactuliem.edu.vn/ckfinder/userfiles/files/17431023420.pdfIn PDF document text
    • http://greatwalledmond.com/ckfinder/userfiles/files/dukeb.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/28591906821.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/zovimuzodudigoloranuje.pdfIn PDF document text
    • https://shop-ecobati.com/medias/upload/files/42466262010.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/2e5e534ee3d25f003c95de139b0904e3/rujikokade.pdfIn PDF document text
    • https://nutricionintravenosa.com/wp-content/plugins/super-forms/uploads/php/files/ac0c91afbc88db891565cabc1590a763/zipofenopuzuwoz.pdfIn PDF document text
    • https://alshamiltrading.com/alshamilfiles/file/sakilalologa.pdfIn PDF document text
    • http://shipsupply.ru/userfiles/files/63234660803.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a299827c07f---bikinedizi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+to+see+call+recording+in+vivoPDF 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_off0000edf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001060a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1060A 17368 bytes
SHA-256: 59ade1ebca5ba6602a39ba6e2ea68add030c058b293ad88e21889f711aad96a2
font_02_sfnt_off0001335e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1335E 10688 bytes
SHA-256: dc97c34e2d6314f4fbdd69d371869bb882849c6d60105637c0d915d233abb36e