Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae81de7f9427939c…

MALICIOUS

PDF

79.3 KB Created: 2021-09-05 23:10:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 1ec2e650ab5eb43db5eb3e7d8548d345 SHA-1: d8d0285f146a4788c903bf0afb224e0b0c6d95f2 SHA-256: ae81de7f9427939cec475590b60fd720ab5dc5ed4cb522e2e0b31489a9b56edd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting it functions as a link farm to distribute malicious content or facilitate phishing. The presence of external URI heuristics further supports the attack pattern of directing users to potentially harmful external resources.

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://philabc.ru/uplcv?utm_term=ets+toeic+test+rc+%EA%B3%B5%EC%8B%9D%EC%8B%A4%EC%A0%84%EC%84%9C+1000+pdf PDF link annotation
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160f1d52387d5f---mevafebitev.pdfIn PDF document text
    • https://ngusacdon.com/upload/files/93446017853.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/b8a5b27662160db9c798a2e9e9be22c4/5618170260.pdfIn PDF document text
    • http://gibisch.info/files/files/redovodi.pdfIn PDF document text
    • http://polletnv.be/uploads/files/3640881219.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160832e2aa8748---69151660527.pdfIn PDF document text
    • https://certifiedcollisionrepair.com/home/cert/public_html/ckfinder/userfiles/files/zukubedelosudagefiseb.pdfIn PDF document text
    • https://armandofalconi.net/userfiles/file/luvezelefivo.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/6406829ddd11ea283fa0cf30ba225c39/59980281551.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a388f001df9---80351976823.pdfIn PDF document text
    • http://caopump.com/admin/userfiles/file/29472763809.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f557ca1615---94011687216.pdfIn PDF document text
    • https://almoheetmanpower.com/public_html/userfiles/file/73797145462.pdfIn PDF document text
    • http://instalacje-elektryczne.net/ckfinder/userfiles/files/fisajotisepa.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1609d12e193c04---bedofozonemukoxu.pdfIn PDF document text
    • http://vestmorecapital.com/images/epost/rutasajegofewibe.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/i9j8k0h8k3l7mfvjmca5htm404/98199973930.pdfIn PDF document text
    • http://alde-pace.org/ckfinder/userfiles/files/manufewibazeruvulekigar.pdfIn PDF document text
    • https://kozmetikadunakeszi.hu/userfiles/file/75950728498.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606f643808a1c---setowugudiritimezowuzik.pdfIn PDF document text
    • http://peak-experience-japan.com/images/blog//file/farogexopu.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/51446262880.pdfIn PDF document text
    • http://knshzj.com/CKEdit/upload/files/kivawewevon.pdfIn PDF document text
    • https://infrapanel-alegjobbfutes.hu/userfiles/file/8497227858.pdfIn PDF document text
    • http://immodraft.nrw/images/architekten_agentur_images_/file/mufukugusijimizi.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_off0000c629.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC629 21448 bytes
SHA-256: 70cfc95bbb80759929f2401eadaa92fe16890233430bf3dd9e5f4345ae65d50e
font_01_sfnt_off0000fdff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDFF 10456 bytes
SHA-256: d8a7167c88a9315ed95caf26f30390e59ba35221215da183b7ea6fa756271f2b
font_02_sfnt_off000115e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1