Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4783b91c91ca445…

MALICIOUS

PDF

81.9 KB Created: 2021-10-07 01:10:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e1430703ed447b33c05a0cb67a745d4a SHA-1: fd1ee9574f8f637f01a9bb3f8200ca5b82918b84 SHA-256: a4783b91c91ca44555865215917f1c129d54889132bf06587960b5ef6cee4e1b
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 WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://crysiq.ru/uplcv?utm_term=camber+alignment+near+me PDF link annotation
    • http://werder-ritter.de/UserFiles/File/39331773276.pdfIn PDF document text
    • http://cauthangdep24h.com/upload/files/20620510574.pdfIn PDF document text
    • https://bor-diing.com/upload/files/rovefelutisi.pdfIn PDF document text
    • http://dlabiura.kbo.pl/ckfinder/userfiles/files/bonojalive.pdfIn PDF document text
    • http://c-amc.com/upload/files/manunuwikugepetuvabi.pdfIn PDF document text
    • https://bharatceramics.in/ckfinder/userfiles/files/62699420036.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1615aa8ce09f23---mepituwovaramenamu.pdfIn PDF document text
    • http://delfosventures.com/userfiles/files/55634658566.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/48938164973.pdfIn PDF document text
    • http://dansungsala.com/uploads/files/13992399859.pdfIn PDF document text
    • http://xn--80aaa1acmiejxr6d7fg.xn--p1ai/data/files/92712190995.pdfIn PDF document text
    • https://askisan.com/upload/ckfinder/files/35879962812.pdfIn PDF document text
    • http://studiopiergentili.it/userfiles/files/vanatotezipej.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/p7e557pq6mhks9vdi898as6385/kowalopobux.pdfIn PDF document text
    • https://maria-galland.ru/files/file/43833143116.pdfIn PDF document text
    • http://prime-standard.com/piceditor/file/zasolarolebunavedipifadi.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/seregawidi.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/136043ed63978c41c3f203fd55b87025/697189543.pdfIn PDF document text
    • http://mextro.de/upload/files/31645272700.pdfIn PDF document text
    • http://gandolfiarchitetti.com/userfiles/files/vuvitusataku.pdfIn PDF document text
    • http://lumieye.com/userData/ebizro_board/file/89691352340.pdfIn PDF document text
    • http://sinproval.it/userfiles/files/mosutivas.pdfIn PDF document text
    • http://henzefashion.com/userfiles/file/32808705838.pdfIn PDF document text
    • https://pilot-nav.socksnbows.com/ckfinder/userfiles/files/kabodilezexap.pdfIn PDF document text
    • http://moderncarrent.com/user_img/files/bigowosekewuvuwenobuba.pdfIn PDF document text
    • 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_off0000d92a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD92A 18840 bytes
SHA-256: 73fcbbd42ca9d0214ac36e81fd0d603871a7a270f279fe002f34c07fa47540ba
font_01_sfnt_off00010aa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000122b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122B7 10332 bytes
SHA-256: 37743aadf21848be82b5f23decda252445d4d8bb00389e66d2988fb9d9d9bc48