Malicious PDF — malware analysis report

Static analysis result for SHA-256 a53ad926ef08d4e2…

MALICIOUS

PDF

96.4 KB Created: 2021-09-06 18:46:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 648682eab02ddb25cdb146b2dba8ff88 SHA-1: 7e76092f5aa615579d0c168c8ee31fe84b5d949e SHA-256: a53ad926ef08d4e24499a18f82759d54cb893e27875ee089c4697b825588e9d1
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a link farm pointing to multiple compromised WordPress upload directories and disposable hosting sites, likely intended to redirect users to phishing or malware distribution pages. The presence of external URIs and link farm heuristics strongly suggests a phishing or social engineering attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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://pixomot.ru/uplcv?utm_term=exercices+conjugaison+pass%C3%A9+compos%C3%A9+cm2+pdf PDF link annotation
    • http://ahcxdq.com/uploads/file/292034432708.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3b975cf9e---jawekemewoworidivejife.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609990bb0c2eb---56750879724.pdfIn PDF document text
    • http://ardechetendancebrut.fr/userfiles/ardechetendancebrut.fr/file/samowakugi.pdfIn PDF document text
    • https://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/1aff678ea1f6006ddf1886ed22b161f4/dewerudotap.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1fdeee0342---62526752637.pdfIn PDF document text
    • https://noriupapildu.lt/ckfinder/userfiles/files/6262665047.pdfIn PDF document text
    • https://alate.org/admin/fckeditor/editorfile/36942372742.pdfIn PDF document text
    • https://loyallcanada.ca/editor_files/file/80255427281.pdfIn PDF document text
    • http://abwpetersburg.com/uploads/files/23046783316.pdfIn PDF document text
    • https://omegaplus.bg/uploads/pages/files/16456972903.pdfIn PDF document text
    • https://www.explosivo.gr/wp-content/plugins/super-forms/uploads/php/files/2c20a8a058c894a38344d246206222c5/30906395745.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16105d9f54876c---valosimegawozinolanejefu.pdfIn PDF document text
    • http://nowator-zpu.pl/userfiles/file/41624013168.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7d8fa33ab---xonedimuwe.pdfIn PDF document text
    • https://medgarlci.com/wp-content/plugins/super-forms/uploads/php/files/ca89011b11bbf40261c49fb01bb30116/9298120591.pdfIn PDF document text
    • https://brukspec.pl/upload/file/61875849428.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/31611643285.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb2784d10cc---podeverezinom.pdfIn PDF document text
    • https://www.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/17cee78a24282fd7c51208ddd0434c36/vufovanuwuzadigi.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/suzasopaji.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/ea461d589e222d9ee5f80b2c63d10b4b/sofedoma.pdfIn PDF document text
    • http://tuclubcr.com/campannas/file/desovidopenuzatow.pdfIn PDF document text
    • https://budapestpainter.hu/ckfinder/userfiles/files/39688334717.pdfIn PDF document text
    • http://opakowania-loga.pl/zdjecia/fotki/file/mekozetaraneg.pdfIn PDF document text
    • http://ccforum.kr/uploads/file/1623018247.pdfIn PDF document text
    • http://digemnd.com/UserFiles/file/sofixepulupowixofirikaz.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_off0001087a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1087A 21488 bytes
SHA-256: 03fcd463d6af88d31418b8495f18c6465a00802b1140433b681e7b6eae47a5fc
font_01_sfnt_off00013eed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015704.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15704 11408 bytes
SHA-256: 9badcd2c054391b84585797c2087d4c9f8ca26692edbc0c0f24d260dfc6d277d